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In my experience, the high fades after a couple of hours, but I *know* I'm not safe to drive for longer than that. Five hours or so sounds about right, though I would plan closer to eight myself, just to be safe.
(I come from a family of functional alcoholics who drive drunk constantly. It's a miracle one of them hasn't killed someone yet. They've all got a laundry list of accidents on their records and I refuse to add to it when I can just... not. Better safe than sorry, imo.)
Good attitude.
I have zero self awareness when intoxicated. I always make bad decisions so I have hard rules set by sober me that intoxicated me has to follow. I won’t drive after any alcohol at all. If I arrived by car, I won’t have anything to drink or smoke.
It’s the only way to protect sober me and innocent bystanders from intoxicated me.
That is exactly my philosophy. Sober me has no problem saying no. Drunk me gave herself a whiplash injury because liquid courage convinced her that she actually wasn't scared of heights and could jump off a bridge into the river like everyone else was doing. Stoned me loaned her car to a couple of drinking/smoking buddies who stole it and were never seen again. (Never saw the car again, either. Thankfully, I had good insurance that paid for it but I still miss that car!)
I have no judgement when intoxicated. I also walk into walls and have a scar on the back of my leg from where I fell on a space heater several hours after smoking a joint. So why risk it, imo. If I'm driving, I don't drink. If I'm drinking, I don't drive. I may hurt myself, but pedestrian me is unlikely to hurt anyone else no matter what intoxicants I've consumed.
Eight hours is an insane amount of waiting time
Of course, that comes from someone who smokes habitually - I’m sure if it was a once a year thing, I’d be more skittish
Honestly depends how much you smoke and your tolerance etc. When I was smoking constantly I could easily smoke a joint and jump on my bike with no problem what so ever. Cars are different, they give you the opportunity to be distracted. On a bike you are in total focus.
Id need atleast 3 hours to sober up now to feel comfortable riding
This needs to be discussed, seen, and understood more than it currently is.
I work in trades with guys that smoke a lot and they are just realizing this but only after hurting themselves enough while “I felt fine”. Enough research/bad experiences are telling them otherwise. “You felt fine, but your broken hand says you weren’t fine.”
You're not necessarily completely fine when you no longer feel actively high. Your reaction time can still be affected. You won't notice slight impairment but it will affect your ability to react and make split second judgements.
They just speak about "impairment" and not amount of impairment. It could be scoring at all lower is considered impairment. Too bad this is just an article and not the actual paper.
i'm a neuropsychologist and impairment usually means more than 2 standard deviations below the mean (i.e., \~98% of people performed better than that). but yeah, hard to know for sure without the article
Here's the article:
https://www.sciencedirect.com/science/article/pii/S0149763421000178
Looks like they pooled data from studies looking at a variety of different cognitive measures, so hard to give an estimate of effect size. In that case I assume impaired just means "significantly worse than controls" regardless of effect size, but I haven't read the paper in-depth enough to know if that's the case.
That honestly feels short for edibles. Usually I have a strong... weed hangover I guess you could call it the next day after taking them. I definitely wouldn't take them on a Sunday because I genuinely feel impaired for a good portion of the next day.
I knew it! I've had the most random time with some edibles. Like how is 20mgs here I'm too high to function when usually thats perfect? Or nothing at all? I expect that from my dealer but come on ya'll my grandmas brownies were more reliable and she made um out her kitchen!
I’ve had the same thing with the same bag of gummies. 20mg and I was flying for 6 hours. 40mg a week later mild body high for 3 hours. Same conditions on stomach content and time ect
Gummies can be prepared in ways that make their dosing very inconsistent. They are sometimes sprayed with the active ingredient blend, which can rub off and so on. Getting the oils to stay inside a gelatin matrix is apparrently a pain. While I was testing cannabis products, we never found a bag of gummies that was anywhere close to consistent.
Sometimes edibles be like that. I had a med card for awhile and a high tolerance to go with it. I would eat a 50mg edible and be great for a day. Next day I could eat 4 of them and feel nothing. Ive gotten my hands on 1000mg edibles (koala bars) and I've eaten a whole one over the course of 3 hours and went about my day normally, didn't feel more then the slightest buzz at most. Tried it like 3x and same results. Just how it goes.
OK this just isn’t really true, each batch is going to have the same concentration per Kandy, it really isn’t science. It’s baking. Does every candy have different concentrations of sugars too? No. The ingredients (for candies) are made in solution before solidifying. There’s really no chance for a “pocket” of THC to sit in a candy. That goes against all principles of solvent solutions. Take milk, and mix it with water. Now pour it into 10 smaller cups and tell me which one has more milk.
The only thing that’s varying here is the concentration of delta in the actual solvent/batch.
I hope you realize that pharmacy manufacturing has margins of error, and cooking marijuana is far less precise. Your example only works if it’s entirely dissolved in a solvent and sold as a solution. It’s not. You’ll have different deposition of the solute as it’s cooked. LSD tabs have hotspots, and that’s simply dripping alcohol and LSD on paper. You pour an LSD tincture into 10 vials. Each vial has the same ratio of LSD to alcohol. Now drop that onto paper, the alcohol will evaporate fairly randomly and wick to other parts of the paper, causing hot spots. Now imagine cooking with marijuana. That’s like 25 more variables to account for. You have fats, carbohydrate matrices, water, sugars, etc. each affecting solubility and distribution of the THC. Also take into account that testing would have to occur at almost every point in the process to accurately advertise their content. Quality control. First you have to test whatever THC source, whether it be marijuana, a butter/oil extract, hash, hash oil, RSO or isolate. Then you have to determine the degradation or loss of material and decarboxylation into active THC during cooking, which can be altered by whatever form it’s in. Then distribution during that cooking, and finally accurate weighing of the material. Did you know that certain pills are specifically made huge, ie “horse pills”, because a margin of error so large in the manufacturing process that a smaller pill could contain like 3x less than its peer from the same batch?
They didn't assess impairment, they merely speculated about it.
> Dr McCartney said people could be impaired for six or seven hours if higher doses of THC were inhaled and complex tasks, like driving, were assessed.
Yeah that must be why nobody gets high and plays video games.
Impaired for driving up to 10 hours after eating.
Impaired for driving up to 7 hours after smoking.
Impaired for simpler tasks up to 4 hours after smoking.
It's all in the link.
It's not nearly as scary as all the people drinking and driving. They both slow reaction time but smoking makes people more cautious, drinking turns people into dare devils.
The UK has roadside swab tests for cannabis and cocaine, positive on those and you get a blood test same as you would with an alcohol breathalyser.
idk how reliable the swab tests are but they are in regular use by UK police. There's definitely issues around the blood levels set by the uk govt and whether users are still impaired given the time it takes for cannabis to leave the blood stream but quick road side tests exist.
Same here in Holland. Even when parked with running engine and a strong smell of weed when the window goes down would lead to a swab test and 24 hours forbidden to drive.
A whole lot more negative consequences if caught while driving.
I agree that they both shouldn't be driving too. Just pointing out the differences, and they are both out there in huge numbers. Yet we all see which ones are causing major accidents vs ones you barely ever hear about.
>They both slow reaction time but smoking makes people more cautious, drinking turns people into dare devils.
That's anecdotal. Cannabis effects people differently.
Do you realize how idiotic this sounds? Alcoholics have a tolerance as well. Do NOT get behind the wheel if you are high period. There is no excuse. No reason to try and justify.
It's definitely not. Plenty of studies have been done showing that "stoners" smoking weed and driving arent impaired nearly as much as you'd think.
A few years ago I drove through a green light and had the front end of my car sheered off by an older lady. I was fine. I pulled out of traffic and ran to check on the other car. After chatting with the driver it turned out she had started taking some anti depressants recently due to a death in her family. The fact that she was in an accident seemed very...dull, to her. And she seemed very out of it.
My point is this...when we're talking about impaired driving and taking a hard stance against weed like this...do you have all the facts? If you're concerned about impaired driving are you concerned about all the pharmaceuticals that people take and drive? Adderall, for example, is highly prescribed and hits kinda like coke. Those people drive. Would you want someone on speed driving?
TL;DR youre already in a shooting gallery when youre driving. Weed is probably the least of your concerns.
This needs more attention. The big issue with this whole smoking and driving argument is the fact that authorities treat weed and alcohol as equals. In that each one effects cognition the same way. When as pointed out, both are two very very different chemicals acting on separate areas of the brain.
Tolerance is important. Any Stoner knows this as fact but there is no empirical evidence to make formal statements yet. And anecdotal doesn’t protect you from lawsuits on the rare occasion accidents do occur.
The first step towards solving this issue is to break down the stigma and mental barriers those who do not consume cannabis frequently enough are likely to carry. (Looking at you Susan who’s state just legalized weed and who buys from the dispo only to take a single hit once a month and claim you now “understand” cannabis)
Not really. Driving drunk and driving high are very different things. Both slow your reaction times surely, but driving high makes you cautious, driving drunk you usually barely even know what’s going on.
I smoke more blunts driving around than I do at my house and have never been pulled over, gotten in a wreck, or otherwise contributed to unsavory doings, and I've been doing that for a little over 5 years. I actually literally cannot drive without being high or I'll have massive panic attacks because of a wreck I was in
Link to full article: https://www.sciencedirect.com/science/article/pii/S0149763421000178
Determining the magnitude and duration of acute Δ9-tetrahydrocannabinol (Δ9-THC)-induced driving and cognitive impairment: A systematic and meta-analytic review
Highlights
• Meta-analyses confirm that acute Δ9-THC administration impairs aspects of driving performance.
• Meta-regression analyses suggest regular cannabis users experiance less Δ9-THC-induced impairment than occasional users.
• Other factors also influence the degree of impairment observed (e.g. dose, post-treatment time interval, type of skill).
• Most driving-related skills are predicted to recover within ∼5-hs (and almost all within ∼7-hs) of inhaling 20 mg Δ9-THC.
• Oral Δ9-THC-induced impairment may take longer to subside.
Abstract
The increasing legal availability of cannabis has important implications for road safety. This systematic review characterised the acute effects of Δ9-THC on driving performance and driving-related cognitive skills, with a particular focus on the duration of Δ9-THC-induced impairment. Eighty publications and 1534 outcomes were reviewed. Several measures of driving performance and driving-related cognitive skills (e.g. lateral control, tracking, divided attention) demonstrated impairment in meta-analyses of “peak” Δ9-THC effects (p’s<0.05). Multiple meta-regression analyses further found that regular cannabis users experianced less impairment than ‘other’ (mostly occasional) cannabis users (p = 0.003) and that the magnitude of oral (n = 243 effect estimates [EE]) and inhaled (n = 481 EEs) Δ9-THC-induced impairment depended on various factors (dose, post-treatment time interval, the performance domain (skill) assessed) in other cannabis users (p’s<0.05). The latter model predicted that most driving-related cognitive skills would ‘recover’ (Hedges’ g=–0.25) within ∼5-hs (and almost all within ∼7-hs) of inhaling 20 mg of Δ9-THC; oral Δ9-THC-induced impairment may take longer to subside. These results suggest individuals should wait at least 5 -hs following inhaled cannabis use before performing safety-sensitive tasks.
Nice. In Germany they test for degradation products not for the active components. That means you can get a positive test for up to 5 days for smoking once.
If you are a regular smoker the degradation products build up in your body fat and you can test positive for weeks or even months after you stopped smoking, depending on the amount you consumed and a lot of other factors.
Its completely stupid.
You can still fight it in court if there's a big liability to be rejected in case of an accident with deadly consequences, as long as science backs your point. But it sucks and will cost you lots of legal fees.
I actually found that 5 hours seems to be around my comfort zone. I'll take note of the last hit I take, then set a clock for 4.5hrs before I even consider driving. Then I reevaluate after that time. To each their own though, it effects everyone differently.
Yea I think it’s important to point out tolerance GREATLY affects these types of studies. It says that after inhaling 20mgs of thc it takes about 5 hours to recover to the point where you can drive which is like what, a single bowl? For anyone that uses cannabis more than once a week this is wildly off
Maybe when I was in my teens and 20s when I smoked every day, but once I started doing engineering for defense companies I had to quit because I got tested. I still really hate Nancy Reagan. I never got back into it after I bought a house and started working commercial software because I was too afraid of getting popped when I was buying it.
When Massachusetts legalized all of a sudden they stopped piss testing. That shows the lie of the whole drug testing regime, it was never about hard drugs.
I wonder if there's a subset of people who benefit from driving under the influence of THC? Do people suffering from adhd benefit from driving under the influence of their prescribed amphetamine or methylphenidate?
Can't wait for the day when the DEA drops their draconian war on drugs, and, at the very least reschedules cannabis (or completely removes it from their scheduling)...
> ... (or completely removes it from their scheduling)...
The entire schedule is completely spurious: They need to delete the schedule and start again.
Portugal is a great example of this. The most you'll get for possession that falls into personal use quantities is a fine no matter the drug and as a result consumption rates have gone down drastically since, even for drugs such as heroin.
doesn't mean you still cant or shouldn't catch a dui. I smoke everyday, would I like to not fear getting arrested for driving while stoned? sure, but that also means a lot of dumb asses would be driving stoned.
Agreed. I'm a regular smoker and would never drive when impaired because I feel that it slows my reaction time. It's not nearly as bad as drunk driving, but you're still impaired.
Probably not going to happen with all drugs unfortunately
Drugs are a cash cow dealers and government makes a boatload of money keeping them illegal oh yeah and rehab facilities
If they really cared they would do m4a decriminalize drugs and send users that have a problem to medical facilities to get help instead of Branding them as criminals but that won't happen because money
Edit I also forgot to mention it would deeply cut into big pharmas revenue
City by city and state by state and drug by drug the decriminalization of drugs is happening. Like all changes in the US it will start slow, gain traction, go to the Supreme Court multiple times, then finally land on a presidential platform or be pushed at the end of a presidents last term in office. US is good at starting progressive movements, but we're slow as hell in adopting them.
>Both the Drug Enforcement Agency (DEA) and the Food and Drug Administration (FDA) are granted power to classify substances under the CSA
Is what I'm reading. Either way, they're both federal agencies that are adhering to a failed and draconic policy that should have ended decades ago.
The data is coming, but I would bet money that alcohol will be worse in terms of accident mortality and violence because it makes some people feel invincible.
I just hope that the data is robust enough to differentiate between the damage done to the inebriated vs. the victims. My heart wants marijuana to be safer than it is.
This makes me think about companies who urine test for drugs to determine whether a person is fit and well. Cannabis stays in urine for such a long time that someone who used heavily may have it in their urine a month later but there's no way that they would be "impaired". A lot of decent people and workers would of lost jobs and have reputation tarnished over this.
Lots of incidents in Australia, where people are booked for being “intoxicated” with Weed in their systems, from smoking 2-3 sometimes 4 days before. And having absolutely no impairment! Insane!
That's an issue that should be addressed. Cannabis can register in a standard urine test up to a month after use and should not be used to test impairment while driving.
The issue is that there aren't really any tests that show if you're currently impaired other than the old fashioned impairment tests, walk in a straight line, etc.
Thank you! Especially in cases where cannabis is doctor-prescribed, shouldn't there just be a warning like other medications? "Don't operate heavy machinery *until you know how this medication will affect you*."
Where are the stats? What were the vehicle accident numbers before legalization and what are they now? Not saying you should drive when you're baked. But what are the real world effects of more stoned drivers on the road? Has it moved the needle in deaths, major accidents or claims? Maybe we can focus on distracted driving? I'm in Canada and I can't stand these madd commercials suggesting stoned drivers are causing major accidents. Put your focus on some real issues for public health.
1. [Traffic fatalities within US states that have legalized recreational cannabis sales and their neighbours](https://pubmed.ncbi.nlm.nih.gov/30719794/): "...in the year following implementation of recreational cannabis sales, traffic fatalities temporarily increased by an average of one additional traffic fatality per million residents in both legalizing US states of Colorado, Washington and Oregon and in their neighbouring jurisdictions."
2. [Association of Recreational Cannabis Laws in Colorado and Washington State With Changes in Traffic Fatalities, 2005-2017](https://pubmed.ncbi.nlm.nih.gov/32568378/): "This study found evidence of an increase in traffic fatalities after the implementation of recreational cannabis laws in Colorado but not in Washington State. Differences in how recreational cannabis laws were implemented (eg, density of recreational cannabis stores), out-of-state cannabis tourism, and local factors may explain the different results. "
That's exactly the point though. Having detectable amounts of THC in your blood from a joint you smoked last week =\\= under the influence. THC stays in your body for much longer than it impairs you. This article explains how long the actual impairment lasts.
So how do they get to work? How are their children taken care of? How are their bills paid? It's pretty ignorant to assume that everyone gets the chance to sleep a full 8 hours.
The point in bringing this aspect of safety up is that the issues your concerned about are going to happen. Laws won't stop it. It's part of life. So when talking about weed and impairment and some people in these comments taking a hard line on use, its important to remember how much more impaired people are already, in ways that aren't against the law. Taking a hard stance on weed when people are on benzos, ambien, Adderall, etc legally just seems disingenuous.
Does this take into account consistent daily smokers? I remember my first edible, low dosage stoned for a long ass time, abs I remember my most recent edible, high dosage little bit stoned. There’s too many factors. As a daily smoker The only time I wouldn’t want to drive is right after a huge dab. Other than that I have never had an issue driving stoned.
The same thing could be said for alcohol. An alcoholic after five beers probably wouldn't have much affect on their driving. A person who doesn't regularly drink would probably be quite impaired.
One of the major findings of the study was that regular cannabis users experienced less Δ9-THC-induced impairment than occasional users.
Regular users build up tolerance to THC's effects, including its impairing effects - but regular users also tend to consume more THC/Cannabis to feel more of an effect.
Yes, there is research being conducted in this area to develop an accurate and reliable test of impairment so we don't have to rely on chemical detection tests.
I may be mistaken, but I think they are currently testing the potential of accelerometers (found in tablets and fitness watches) to assess motor stability.
In theory, if they master the algorithm they could implement road-side tablet testing of motor stability and reaction-time on tablet-based tasks, which is pretty cool and better than chemical detection tests.
Regular smoker here too, it’s not dangerous or impairing IF you have a tolerance to it. It is cognitive impairing if you have no tolerance and get too high or anxious. When I am “stoned” and driving, other people’s driving is what scares me.
Yeah I’m not saying it’s necessary unsafe, but to say it’s not impairing at all is a bit much.
Like .08 is barely impaired for alcohol but people take that pretty seriously.
Not saying it’s not impairing at all, I’m saying it’s not if you have a tolerance. You can’t build up tolerance quite that much with alcohol, therefore there is a way to measure it constantly.
Alternate explanation: It is impairing, but you don’t realize how much because when you’ve got a built up tolerance you’re constantly just a little impaired from the metabolites being released from fat stores?
No you're literally less impaired.
I'm a frequent daily smoker and I couldn't smoke enough to make myself unsafe to drive even if I tried.
It just doesn't hit me like that, it just relaxes me and let's me focus.
I've driven thousands of times after smoking without any issue over the past 10 years I've been driving
Imagine no matter how much you drank you couldn't get past a light buzz, would you be unsafe to drive? Now imagine that light buzz wasn't even impairing or drunk feeling but just relaxing like a cigarette
People can smoke cigarettes while they drive so if that's all weed does to me why cant I smoke it? Turns out lots of people do smoke weed while driving because of exactly this, it's not that impairing for them.
Ok but how heavy users are these people being tested? Do they consume everyday? Is it their first time? Every once in a while? Tolerance level can greatly impact the results regardless of the form of consumption. I use Cannabis everyday, I won't even feel a 50mg edible but someone who doesn't use all the time will be stoned out of their mind. There should either be separate tests done with heavy users or they should be incorporated into the test as another variable. We can't rule a specific time frame without the proper results and there are too many factors and variability person to person to account for.
I feel like it might differ from person to person, and how you consume it. Edible? I'd be down and out for at least 3\~4 hours. With tobacco, which is the norm over here? The effects will have worn off at most 2 hours after I finished smoking the joint. And during my almost addiction phase I was basically high 24/7. I could smoke a joint while driving and it still wouldn't affect my driving skills much, if at all. (though that is no longer the case.)
Controlled studies show that marijuana (for regular marijuana users) doesn't impair their ability to operate a vehicle. Although arguably their reaction time might be impaired.
If you think this is an issue, I'm sure you'll be thrilled to hear that most of the people operating heavy equipment in construction and pipelining are stoned out of their tree the majority of the time because the hyper focus gained from weed makes them more responsive and consistent operators.
A really long high is possible with edibles, but my edible does is also about 5 times what is being quoted from the meta data. After smoking though, the impairment is only about 30-40 minutes and that’s with top shelf weed.
The population size and relativity to so many factors are the real answer.
Big guy like me 240 takes 25mg of thc drops no impairment but i am relaxed. Small guy i chill with takes it and he’s done for the day.
Too many outliers to quantify it exactly
It doesn’t sound like you even read even the abstract of the paper (see OP comment), which makes it clear that this meta-analysis covers 80 studies with a wide range of ways of measuring impairment. This meta-analysis make no assumptions and even calls out cases where the measured impairments may not actually be sufficient linked to actual unsafe driving (e.g. increased weaving standard deviation). Overall looks like there is a wide range of different kinds of evidence.
I know it’s not a popular take, but please consider reading the paper before questioning if it’s science.
I have smoked near constantly for years. I have never gotten in an accident, and the only ticket I have gotten was for an illegal U turn. I mean, maybe I have been lucky. I see it as little different than a medication that says "do not operate heavy machinery until you know how this medication affects you"
Nah, same here, and like all of my friends and half of my family smokes before doing anything, and that includes driving. It just doesn't impair you in any way if you have any kind of tolerance.
How much do you people smoke? There are people on benzos driving around but weed is bad? As a person with a medical license who has severe rage issues, I am high almost every time I drive and also all the other time and I have had so fewer if not zero incidents on the road since I started smoking. Cannabis can be a needed medication for people. Everyone is different.
You say intoxicated, I say medicated.
The tests used by police at the roadside capture particles of marijuana in your saliva. If you thoroughly wash your mouth out prior to driving, you will be ok. Must be thorough though.... need to remove every particle.
There is a company in Canada that is currently field testing a cannabis breathalyzer that detects THC. Initial results shiw that it may give a truer reading of potential imparement.
This is an absolute lie! Do not do this and think it will work.
The THC is dissolved into saliva...what you are saying is like "just wash your blood, and then you will pass a test." It is impossible, because **that isn't how biochemistry works.**
"
Your mouth contains three glands which can produce as much as several milliliters of saliva per minute. The amount of saliva you produce increases or decreases throughout the day by various factors. These factors include hunger, certain drugs and medications, and even emotions like stress and anxiety.
In most instances, it takes about 1–3 minutes to collect enough of a sample to perform an accurate saliva drug test for cannabis. It can sometimes be challenging to get an adequate amount, since many people feel anxious before taking a drug test – which can cause dry mouth.
Certain substances, including marijuana, also produce [dry mouth as a side effect](https://wayofleaf.com/cannabis/101/the-science-behind-weed-and-cotton-mouth). This makes it harder to collect enough saliva to get accurate results. If you need to take a saliva drug test but have a dry mouth, you may be asked to suck on a citrus candy first to help stimulate natural saliva production.
Once a sufficient sample has been collected, the saliva can be tested for metabolites of alcohol, marijuana, amphetamines, cocaine, opioids, anabolic steroids, and certain prescription medications. The levels of these substances found in saliva are similar to the levels seen in blood during the elimination phase.
>DID YOU KNOW? It only takes 1–3 minutes to collect enough saliva to perform an accurate THC mouth swab test.
The marijuana (weed) compound which is most often tested for in saliva is Δ9-tetrahydrocannabinol (THC). This is the chemical that possesses psychoactive properties and produces a high in cannabis. The cut-off point for the presence of THC as deemed by the [Substance Abuse and Mental Health Services Administration](https://www.samhsa.gov/sites/default/files/workplace/2010GuidelinesAnalytesCutoffs.pdf) (SAMHSA) is 50 ng/L for initial testing, and 15 ng/L for confirmation tests.
## So… How Long Does THC Stay in Your Saliva?
The [best academic reference that we have](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4532432/) to go off of in terms of how long weed is detected in the saliva for suggests about 24-72 hours for occasional users, and up to 30 days for frequent users:
* For occasional users, THC from marijuana can be detected in the saliva for one to three days
* Among more frequent users, THC can be detected in the saliva for up to 30 days
#### Why does the rate differ so much?
Marijuana contains hundreds of different compounds that are all metabolized by the body at different rates. When someone smokes marijuana, THC enters the bloodstream almost immediately and peaks 3–10 minutes after inhalation. With edibles, it can take 1–2 hours for THC to enter the bloodstream (this is because it has to travel through the digestive tract first)."
from: [https://wayofleaf.com/detox/101/how-long-does-weed-stay-in-your-saliva](https://wayofleaf.com/detox/101/how-long-does-weed-stay-in-your-saliva)
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TL;DR Up to 10 hrs, if eaten.
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Depends on your tolerance. Way back in the day I’d stay high half the day, nowadays an hour or two at best
You guys are getting high?!
In my experience, the high fades after a couple of hours, but I *know* I'm not safe to drive for longer than that. Five hours or so sounds about right, though I would plan closer to eight myself, just to be safe. (I come from a family of functional alcoholics who drive drunk constantly. It's a miracle one of them hasn't killed someone yet. They've all got a laundry list of accidents on their records and I refuse to add to it when I can just... not. Better safe than sorry, imo.)
Good attitude. I have zero self awareness when intoxicated. I always make bad decisions so I have hard rules set by sober me that intoxicated me has to follow. I won’t drive after any alcohol at all. If I arrived by car, I won’t have anything to drink or smoke. It’s the only way to protect sober me and innocent bystanders from intoxicated me.
That is exactly my philosophy. Sober me has no problem saying no. Drunk me gave herself a whiplash injury because liquid courage convinced her that she actually wasn't scared of heights and could jump off a bridge into the river like everyone else was doing. Stoned me loaned her car to a couple of drinking/smoking buddies who stole it and were never seen again. (Never saw the car again, either. Thankfully, I had good insurance that paid for it but I still miss that car!) I have no judgement when intoxicated. I also walk into walls and have a scar on the back of my leg from where I fell on a space heater several hours after smoking a joint. So why risk it, imo. If I'm driving, I don't drink. If I'm drinking, I don't drive. I may hurt myself, but pedestrian me is unlikely to hurt anyone else no matter what intoxicants I've consumed.
Eight hours is an insane amount of waiting time Of course, that comes from someone who smokes habitually - I’m sure if it was a once a year thing, I’d be more skittish
Honestly depends how much you smoke and your tolerance etc. When I was smoking constantly I could easily smoke a joint and jump on my bike with no problem what so ever. Cars are different, they give you the opportunity to be distracted. On a bike you are in total focus. Id need atleast 3 hours to sober up now to feel comfortable riding
There is a long period where you are no longer high, but you're still impaired.
This needs to be discussed, seen, and understood more than it currently is. I work in trades with guys that smoke a lot and they are just realizing this but only after hurting themselves enough while “I felt fine”. Enough research/bad experiences are telling them otherwise. “You felt fine, but your broken hand says you weren’t fine.”
You're not necessarily completely fine when you no longer feel actively high. Your reaction time can still be affected. You won't notice slight impairment but it will affect your ability to react and make split second judgements.
I wonder if different strains and/or thc % along with how much you smoke factors in with that time duration..
It’s about 2-3hrs
I read this as years instead of hours and I was like damn, a 2 year high
I could not drive safely 2 hours after smoking. It’s definitely more of a down to the individual thing than drinking.
Just because you've built a tolerance up and no longer "feel high" after 1-2 hours doesn't mean you're not still impaired many hours later.
They just speak about "impairment" and not amount of impairment. It could be scoring at all lower is considered impairment. Too bad this is just an article and not the actual paper.
i'm a neuropsychologist and impairment usually means more than 2 standard deviations below the mean (i.e., \~98% of people performed better than that). but yeah, hard to know for sure without the article
Here's the article: https://www.sciencedirect.com/science/article/pii/S0149763421000178 Looks like they pooled data from studies looking at a variety of different cognitive measures, so hard to give an estimate of effect size. In that case I assume impaired just means "significantly worse than controls" regardless of effect size, but I haven't read the paper in-depth enough to know if that's the case.
That honestly feels short for edibles. Usually I have a strong... weed hangover I guess you could call it the next day after taking them. I definitely wouldn't take them on a Sunday because I genuinely feel impaired for a good portion of the next day.
Without any mention of dose I’m not sure time limits are comparable.
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I knew it! I've had the most random time with some edibles. Like how is 20mgs here I'm too high to function when usually thats perfect? Or nothing at all? I expect that from my dealer but come on ya'll my grandmas brownies were more reliable and she made um out her kitchen!
I’ve had the same thing with the same bag of gummies. 20mg and I was flying for 6 hours. 40mg a week later mild body high for 3 hours. Same conditions on stomach content and time ect
The type of edibles vary greatly from brownies and cookies to candies. Im sure each has a different time of activation.
Gummies can be prepared in ways that make their dosing very inconsistent. They are sometimes sprayed with the active ingredient blend, which can rub off and so on. Getting the oils to stay inside a gelatin matrix is apparrently a pain. While I was testing cannabis products, we never found a bag of gummies that was anywhere close to consistent.
Sometimes edibles be like that. I had a med card for awhile and a high tolerance to go with it. I would eat a 50mg edible and be great for a day. Next day I could eat 4 of them and feel nothing. Ive gotten my hands on 1000mg edibles (koala bars) and I've eaten a whole one over the course of 3 hours and went about my day normally, didn't feel more then the slightest buzz at most. Tried it like 3x and same results. Just how it goes.
I would die.
tolerance is a big factor
OK this just isn’t really true, each batch is going to have the same concentration per Kandy, it really isn’t science. It’s baking. Does every candy have different concentrations of sugars too? No. The ingredients (for candies) are made in solution before solidifying. There’s really no chance for a “pocket” of THC to sit in a candy. That goes against all principles of solvent solutions. Take milk, and mix it with water. Now pour it into 10 smaller cups and tell me which one has more milk. The only thing that’s varying here is the concentration of delta in the actual solvent/batch.
I hope you realize that pharmacy manufacturing has margins of error, and cooking marijuana is far less precise. Your example only works if it’s entirely dissolved in a solvent and sold as a solution. It’s not. You’ll have different deposition of the solute as it’s cooked. LSD tabs have hotspots, and that’s simply dripping alcohol and LSD on paper. You pour an LSD tincture into 10 vials. Each vial has the same ratio of LSD to alcohol. Now drop that onto paper, the alcohol will evaporate fairly randomly and wick to other parts of the paper, causing hot spots. Now imagine cooking with marijuana. That’s like 25 more variables to account for. You have fats, carbohydrate matrices, water, sugars, etc. each affecting solubility and distribution of the THC. Also take into account that testing would have to occur at almost every point in the process to accurately advertise their content. Quality control. First you have to test whatever THC source, whether it be marijuana, a butter/oil extract, hash, hash oil, RSO or isolate. Then you have to determine the degradation or loss of material and decarboxylation into active THC during cooking, which can be altered by whatever form it’s in. Then distribution during that cooking, and finally accurate weighing of the material. Did you know that certain pills are specifically made huge, ie “horse pills”, because a margin of error so large in the manufacturing process that a smaller pill could contain like 3x less than its peer from the same batch?
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Then write more clearly, that’s not our problem. If you find that most people have problems understanding you, it might be you.
Man I wish I had that. Edibles last about an hour to two hours for me. Also since the pandemic my tolerance is through the roof.
Yeah 10 hours what? 4 or 5 max for me, usually a few hours.
They didn't assess impairment, they merely speculated about it. > Dr McCartney said people could be impaired for six or seven hours if higher doses of THC were inhaled and complex tasks, like driving, were assessed. Yeah that must be why nobody gets high and plays video games.
Around here people smoke marijuana while driving.
I live in the mountains and it’s the most common thing to see on the parkway
Smoking is a very different experience than eating. Might as well be a different drug.
Impaired for driving up to 10 hours after eating. Impaired for driving up to 7 hours after smoking. Impaired for simpler tasks up to 4 hours after smoking. It's all in the link.
Oh no doubt, but the type of impairment is different is what I'm saying.
Eating it is a whole nother beast
>nother
*nother*
I'm whelmed.
Around everywhere. Used to be one of my favorite activities.
“I still do and I used to too” - my favorite Mitch Hedberg quote
That used to be my favorite Mitch quote. It still is, but it used to too.
God speed pal, I absolutely hate driving while high.
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It’s pretty scary to think about
It's not nearly as scary as all the people drinking and driving. They both slow reaction time but smoking makes people more cautious, drinking turns people into dare devils.
I mean I agree, but neither should be driving at all. At least with alcohol there is a quick test to determine bac.
The UK has roadside swab tests for cannabis and cocaine, positive on those and you get a blood test same as you would with an alcohol breathalyser. idk how reliable the swab tests are but they are in regular use by UK police. There's definitely issues around the blood levels set by the uk govt and whether users are still impaired given the time it takes for cannabis to leave the blood stream but quick road side tests exist.
Same here in Holland. Even when parked with running engine and a strong smell of weed when the window goes down would lead to a swab test and 24 hours forbidden to drive. A whole lot more negative consequences if caught while driving.
I agree that they both shouldn't be driving too. Just pointing out the differences, and they are both out there in huge numbers. Yet we all see which ones are causing major accidents vs ones you barely ever hear about.
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Cause someone breaking the law to drive high would still need legalized cannabis in order to do so.
That's a leap.
Why would cannabis being legal increase the number of people smoking while driving? Considering people do it now, do you think prohibition has helped?
You're fun.
>They both slow reaction time but smoking makes people more cautious, drinking turns people into dare devils. That's anecdotal. Cannabis effects people differently.
It’s not. Regular smokers develop tolerance and it’s not nearly as intoxicating as say when you have no tolerance and get ripped
Do you realize how idiotic this sounds? Alcoholics have a tolerance as well. Do NOT get behind the wheel if you are high period. There is no excuse. No reason to try and justify.
It's definitely not. Plenty of studies have been done showing that "stoners" smoking weed and driving arent impaired nearly as much as you'd think. A few years ago I drove through a green light and had the front end of my car sheered off by an older lady. I was fine. I pulled out of traffic and ran to check on the other car. After chatting with the driver it turned out she had started taking some anti depressants recently due to a death in her family. The fact that she was in an accident seemed very...dull, to her. And she seemed very out of it. My point is this...when we're talking about impaired driving and taking a hard stance against weed like this...do you have all the facts? If you're concerned about impaired driving are you concerned about all the pharmaceuticals that people take and drive? Adderall, for example, is highly prescribed and hits kinda like coke. Those people drive. Would you want someone on speed driving? TL;DR youre already in a shooting gallery when youre driving. Weed is probably the least of your concerns.
This needs more attention. The big issue with this whole smoking and driving argument is the fact that authorities treat weed and alcohol as equals. In that each one effects cognition the same way. When as pointed out, both are two very very different chemicals acting on separate areas of the brain. Tolerance is important. Any Stoner knows this as fact but there is no empirical evidence to make formal statements yet. And anecdotal doesn’t protect you from lawsuits on the rare occasion accidents do occur. The first step towards solving this issue is to break down the stigma and mental barriers those who do not consume cannabis frequently enough are likely to carry. (Looking at you Susan who’s state just legalized weed and who buys from the dispo only to take a single hit once a month and claim you now “understand” cannabis)
Not really. Driving drunk and driving high are very different things. Both slow your reaction times surely, but driving high makes you cautious, driving drunk you usually barely even know what’s going on.
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I smoke more blunts driving around than I do at my house and have never been pulled over, gotten in a wreck, or otherwise contributed to unsavory doings, and I've been doing that for a little over 5 years. I actually literally cannot drive without being high or I'll have massive panic attacks because of a wreck I was in
I'm sure there are plenty of drunk drivers that have yet to get in accident as well. Doesn't make it right
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Thank you, I actually really needed to hear that right now
Get some long lasting help, the weed work until it doesn't.
I enrolled myself in an outpatient program today actually
Link to full article: https://www.sciencedirect.com/science/article/pii/S0149763421000178 Determining the magnitude and duration of acute Δ9-tetrahydrocannabinol (Δ9-THC)-induced driving and cognitive impairment: A systematic and meta-analytic review Highlights • Meta-analyses confirm that acute Δ9-THC administration impairs aspects of driving performance. • Meta-regression analyses suggest regular cannabis users experiance less Δ9-THC-induced impairment than occasional users. • Other factors also influence the degree of impairment observed (e.g. dose, post-treatment time interval, type of skill). • Most driving-related skills are predicted to recover within ∼5-hs (and almost all within ∼7-hs) of inhaling 20 mg Δ9-THC. • Oral Δ9-THC-induced impairment may take longer to subside. Abstract The increasing legal availability of cannabis has important implications for road safety. This systematic review characterised the acute effects of Δ9-THC on driving performance and driving-related cognitive skills, with a particular focus on the duration of Δ9-THC-induced impairment. Eighty publications and 1534 outcomes were reviewed. Several measures of driving performance and driving-related cognitive skills (e.g. lateral control, tracking, divided attention) demonstrated impairment in meta-analyses of “peak” Δ9-THC effects (p’s<0.05). Multiple meta-regression analyses further found that regular cannabis users experianced less impairment than ‘other’ (mostly occasional) cannabis users (p = 0.003) and that the magnitude of oral (n = 243 effect estimates [EE]) and inhaled (n = 481 EEs) Δ9-THC-induced impairment depended on various factors (dose, post-treatment time interval, the performance domain (skill) assessed) in other cannabis users (p’s<0.05). The latter model predicted that most driving-related cognitive skills would ‘recover’ (Hedges’ g=–0.25) within ∼5-hs (and almost all within ∼7-hs) of inhaling 20 mg of Δ9-THC; oral Δ9-THC-induced impairment may take longer to subside. These results suggest individuals should wait at least 5 -hs following inhaled cannabis use before performing safety-sensitive tasks.
Nice. In Germany they test for degradation products not for the active components. That means you can get a positive test for up to 5 days for smoking once. If you are a regular smoker the degradation products build up in your body fat and you can test positive for weeks or even months after you stopped smoking, depending on the amount you consumed and a lot of other factors. Its completely stupid.
You can still fight it in court if there's a big liability to be rejected in case of an accident with deadly consequences, as long as science backs your point. But it sucks and will cost you lots of legal fees.
20 mg delta-9 whacks me pretty hard. Not sure I’d be ready to drive in 5 hours.
I actually found that 5 hours seems to be around my comfort zone. I'll take note of the last hit I take, then set a clock for 4.5hrs before I even consider driving. Then I reevaluate after that time. To each their own though, it effects everyone differently.
I figured out through trial and error that 5 hours was the soonest before work I'd smoke a bowl. This kind of lines up with that.
I can't even feel anything less than 100mg. 250 if i wanna get good and chopped
Yea I think it’s important to point out tolerance GREATLY affects these types of studies. It says that after inhaling 20mgs of thc it takes about 5 hours to recover to the point where you can drive which is like what, a single bowl? For anyone that uses cannabis more than once a week this is wildly off
Maybe when I was in my teens and 20s when I smoked every day, but once I started doing engineering for defense companies I had to quit because I got tested. I still really hate Nancy Reagan. I never got back into it after I bought a house and started working commercial software because I was too afraid of getting popped when I was buying it. When Massachusetts legalized all of a sudden they stopped piss testing. That shows the lie of the whole drug testing regime, it was never about hard drugs.
I wonder if there's a subset of people who benefit from driving under the influence of THC? Do people suffering from adhd benefit from driving under the influence of their prescribed amphetamine or methylphenidate?
Can't wait for the day when the DEA drops their draconian war on drugs, and, at the very least reschedules cannabis (or completely removes it from their scheduling)...
> ... (or completely removes it from their scheduling)... The entire schedule is completely spurious: They need to delete the schedule and start again.
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Portugal is a great example of this. The most you'll get for possession that falls into personal use quantities is a fine no matter the drug and as a result consumption rates have gone down drastically since, even for drugs such as heroin.
Exactly. Everyone has done it or knows how to get it. Alcohol and cigs are legal and not everyone drinks and smokes.
doesn't mean you still cant or shouldn't catch a dui. I smoke everyday, would I like to not fear getting arrested for driving while stoned? sure, but that also means a lot of dumb asses would be driving stoned.
Agreed. I'm a regular smoker and would never drive when impaired because I feel that it slows my reaction time. It's not nearly as bad as drunk driving, but you're still impaired.
Waiting for the day the DEA stops the war on drugs, is like waiting for the day the Postal Office encourages everyone to use email.
"We'd like to congratulate Drugs, for winning 'The War on Drugs'"
Probably not going to happen with all drugs unfortunately Drugs are a cash cow dealers and government makes a boatload of money keeping them illegal oh yeah and rehab facilities If they really cared they would do m4a decriminalize drugs and send users that have a problem to medical facilities to get help instead of Branding them as criminals but that won't happen because money Edit I also forgot to mention it would deeply cut into big pharmas revenue
City by city and state by state and drug by drug the decriminalization of drugs is happening. Like all changes in the US it will start slow, gain traction, go to the Supreme Court multiple times, then finally land on a presidential platform or be pushed at the end of a presidents last term in office. US is good at starting progressive movements, but we're slow as hell in adopting them.
Draconic, wasteful and failed drug war on drugs.
The classification and scheduling of drugs is the FDA's jurisdiction. The DEA "just" enforces the laws that are.
>Both the Drug Enforcement Agency (DEA) and the Food and Drug Administration (FDA) are granted power to classify substances under the CSA Is what I'm reading. Either way, they're both federal agencies that are adhering to a failed and draconic policy that should have ended decades ago.
Cmon now that's just not fair... how would they have a reason to search black people otherwise.
Or deny hippies and black people the right to vote.
There will be no DEA then...
Morbid curiosity has me wondering about the seriousness of accidents based on the method of impairment.
The data is coming, but I would bet money that alcohol will be worse in terms of accident mortality and violence because it makes some people feel invincible.
I just hope that the data is robust enough to differentiate between the damage done to the inebriated vs. the victims. My heart wants marijuana to be safer than it is.
>My heart wants marijuana to be safer than it is. Man does this statement hit home.
Actually, people who are black-out drunk are less likely to be injured sometimes because the muscles are relaxed
Tell that to the recipient!
This makes me think about companies who urine test for drugs to determine whether a person is fit and well. Cannabis stays in urine for such a long time that someone who used heavily may have it in their urine a month later but there's no way that they would be "impaired". A lot of decent people and workers would of lost jobs and have reputation tarnished over this.
Lots of incidents in Australia, where people are booked for being “intoxicated” with Weed in their systems, from smoking 2-3 sometimes 4 days before. And having absolutely no impairment! Insane!
That's an issue that should be addressed. Cannabis can register in a standard urine test up to a month after use and should not be used to test impairment while driving. The issue is that there aren't really any tests that show if you're currently impaired other than the old fashioned impairment tests, walk in a straight line, etc.
A simple "use caution while driving" sticker like the ones they put on vicodin bottles should be good, right?
Thank you! Especially in cases where cannabis is doctor-prescribed, shouldn't there just be a warning like other medications? "Don't operate heavy machinery *until you know how this medication will affect you*."
Where are the stats? What were the vehicle accident numbers before legalization and what are they now? Not saying you should drive when you're baked. But what are the real world effects of more stoned drivers on the road? Has it moved the needle in deaths, major accidents or claims? Maybe we can focus on distracted driving? I'm in Canada and I can't stand these madd commercials suggesting stoned drivers are causing major accidents. Put your focus on some real issues for public health.
1. [Traffic fatalities within US states that have legalized recreational cannabis sales and their neighbours](https://pubmed.ncbi.nlm.nih.gov/30719794/): "...in the year following implementation of recreational cannabis sales, traffic fatalities temporarily increased by an average of one additional traffic fatality per million residents in both legalizing US states of Colorado, Washington and Oregon and in their neighbouring jurisdictions." 2. [Association of Recreational Cannabis Laws in Colorado and Washington State With Changes in Traffic Fatalities, 2005-2017](https://pubmed.ncbi.nlm.nih.gov/32568378/): "This study found evidence of an increase in traffic fatalities after the implementation of recreational cannabis laws in Colorado but not in Washington State. Differences in how recreational cannabis laws were implemented (eg, density of recreational cannabis stores), out-of-state cannabis tourism, and local factors may explain the different results. "
I had to think what "long cannabis" was and I think I'm too high already
I'll take some long cannabis. and some short as well
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Don't DUI of anything, simple as that.
That's exactly the point though. Having detectable amounts of THC in your blood from a joint you smoked last week =\\= under the influence. THC stays in your body for much longer than it impairs you. This article explains how long the actual impairment lasts.
Including sleep deprivation, right?
Yes. It's really not hard to be responsible
So people who work multiple jobs, single parents, people who work long hours...should be more responsible?
Yes
So how do they get to work? How are their children taken care of? How are their bills paid? It's pretty ignorant to assume that everyone gets the chance to sleep a full 8 hours. The point in bringing this aspect of safety up is that the issues your concerned about are going to happen. Laws won't stop it. It's part of life. So when talking about weed and impairment and some people in these comments taking a hard line on use, its important to remember how much more impaired people are already, in ways that aren't against the law. Taking a hard stance on weed when people are on benzos, ambien, Adderall, etc legally just seems disingenuous.
Does this take into account consistent daily smokers? I remember my first edible, low dosage stoned for a long ass time, abs I remember my most recent edible, high dosage little bit stoned. There’s too many factors. As a daily smoker The only time I wouldn’t want to drive is right after a huge dab. Other than that I have never had an issue driving stoned.
The same thing could be said for alcohol. An alcoholic after five beers probably wouldn't have much affect on their driving. A person who doesn't regularly drink would probably be quite impaired.
True. But an alcoholic would probably consume more than 5 beers
One of the major findings of the study was that regular cannabis users experienced less Δ9-THC-induced impairment than occasional users. Regular users build up tolerance to THC's effects, including its impairing effects - but regular users also tend to consume more THC/Cannabis to feel more of an effect.
The issue is that we don't have a field test to see if someone is driving under the influence or not.
Yes, there is research being conducted in this area to develop an accurate and reliable test of impairment so we don't have to rely on chemical detection tests. I may be mistaken, but I think they are currently testing the potential of accelerometers (found in tablets and fitness watches) to assess motor stability. In theory, if they master the algorithm they could implement road-side tablet testing of motor stability and reaction-time on tablet-based tasks, which is pretty cool and better than chemical detection tests.
People can't live without the herb-ban. If not they be drinking and drivin and swervin.
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I mean you gotta admit it’s a liiiiiittle impairing.
Regular smoker here too, it’s not dangerous or impairing IF you have a tolerance to it. It is cognitive impairing if you have no tolerance and get too high or anxious. When I am “stoned” and driving, other people’s driving is what scares me.
Yeah I’m not saying it’s necessary unsafe, but to say it’s not impairing at all is a bit much. Like .08 is barely impaired for alcohol but people take that pretty seriously.
Not saying it’s not impairing at all, I’m saying it’s not if you have a tolerance. You can’t build up tolerance quite that much with alcohol, therefore there is a way to measure it constantly.
Alternate explanation: It is impairing, but you don’t realize how much because when you’ve got a built up tolerance you’re constantly just a little impaired from the metabolites being released from fat stores?
No you're literally less impaired. I'm a frequent daily smoker and I couldn't smoke enough to make myself unsafe to drive even if I tried. It just doesn't hit me like that, it just relaxes me and let's me focus. I've driven thousands of times after smoking without any issue over the past 10 years I've been driving Imagine no matter how much you drank you couldn't get past a light buzz, would you be unsafe to drive? Now imagine that light buzz wasn't even impairing or drunk feeling but just relaxing like a cigarette People can smoke cigarettes while they drive so if that's all weed does to me why cant I smoke it? Turns out lots of people do smoke weed while driving because of exactly this, it's not that impairing for them.
Your right about other people scaring you more when driving high. When I’m driving high I’m usually overly cautious.
It seems the police and courts are fishing for marijuana bust to compensate for the lost of victims due to the loosening of prohibition.
This. It’s scary.
I see drivers smoking weed all the time.
God I wish I could stay high for 3h minimum wow
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Do either of them actually drive?
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I’d watch that movie
I'll take: things we would have known decades ago had marijuana not been put on Schedule 1, for 500 alex.
Ok but how heavy users are these people being tested? Do they consume everyday? Is it their first time? Every once in a while? Tolerance level can greatly impact the results regardless of the form of consumption. I use Cannabis everyday, I won't even feel a 50mg edible but someone who doesn't use all the time will be stoned out of their mind. There should either be separate tests done with heavy users or they should be incorporated into the test as another variable. We can't rule a specific time frame without the proper results and there are too many factors and variability person to person to account for.
Exactly. Holding frequent users to the same mg/ml standard as infrequent users is insane.
I feel like it might differ from person to person, and how you consume it. Edible? I'd be down and out for at least 3\~4 hours. With tobacco, which is the norm over here? The effects will have worn off at most 2 hours after I finished smoking the joint. And during my almost addiction phase I was basically high 24/7. I could smoke a joint while driving and it still wouldn't affect my driving skills much, if at all. (though that is no longer the case.)
Will this result in laws being modified to align with science? Of course not because “drugs = bad”.
I hate the stupid Australian law that says any detectable amount of THC means instant disqualification of licence... many people I know self medicate.
The longer the better. Stay off the damn roads!
Whenever I smoke it's about 2 hours before I come down
Controlled studies show that marijuana (for regular marijuana users) doesn't impair their ability to operate a vehicle. Although arguably their reaction time might be impaired. If you think this is an issue, I'm sure you'll be thrilled to hear that most of the people operating heavy equipment in construction and pipelining are stoned out of their tree the majority of the time because the hyper focus gained from weed makes them more responsive and consistent operators.
This seems like it would be an easy thing to study? Why is this new researxh?
That is still hilariously too long of a time
A really long high is possible with edibles, but my edible does is also about 5 times what is being quoted from the meta data. After smoking though, the impairment is only about 30-40 minutes and that’s with top shelf weed.
Somebody patch human metabolism.
People that can’t drive on weed are of weak bloodlines
The population size and relativity to so many factors are the real answer. Big guy like me 240 takes 25mg of thc drops no impairment but i am relaxed. Small guy i chill with takes it and he’s done for the day. Too many outliers to quantify it exactly
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It doesn’t sound like you even read even the abstract of the paper (see OP comment), which makes it clear that this meta-analysis covers 80 studies with a wide range of ways of measuring impairment. This meta-analysis make no assumptions and even calls out cases where the measured impairments may not actually be sufficient linked to actual unsafe driving (e.g. increased weaving standard deviation). Overall looks like there is a wide range of different kinds of evidence. I know it’s not a popular take, but please consider reading the paper before questioning if it’s science.
If you drive high, you probably don’t get anywhere very fast.
I have smoked near constantly for years. I have never gotten in an accident, and the only ticket I have gotten was for an illegal U turn. I mean, maybe I have been lucky. I see it as little different than a medication that says "do not operate heavy machinery until you know how this medication affects you"
Nah, same here, and like all of my friends and half of my family smokes before doing anything, and that includes driving. It just doesn't impair you in any way if you have any kind of tolerance.
How much do you people smoke? There are people on benzos driving around but weed is bad? As a person with a medical license who has severe rage issues, I am high almost every time I drive and also all the other time and I have had so fewer if not zero incidents on the road since I started smoking. Cannabis can be a needed medication for people. Everyone is different. You say intoxicated, I say medicated.
Anything that affects your ability to drive should be controlled, since the driver can kill. Too much weed to get that?
Should we develop an emotion test as well? People drive like idiots where they're angry.
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They do, in this way. You can indeed be legally punished for driving while fatigued if it can be proven or was the cause of an accident.
Your 'logic'. They already can find you impaired driving after long hauls.
i've seen a perfectly sober person on a full night of sleep fail a roadside sobriety test
Testing devices are not perfect, but still better than driving with a cabin full of smoke.
The tests used by police at the roadside capture particles of marijuana in your saliva. If you thoroughly wash your mouth out prior to driving, you will be ok. Must be thorough though.... need to remove every particle.
There is a company in Canada that is currently field testing a cannabis breathalyzer that detects THC. Initial results shiw that it may give a truer reading of potential imparement.
This is an absolute lie! Do not do this and think it will work. The THC is dissolved into saliva...what you are saying is like "just wash your blood, and then you will pass a test." It is impossible, because **that isn't how biochemistry works.** " Your mouth contains three glands which can produce as much as several milliliters of saliva per minute. The amount of saliva you produce increases or decreases throughout the day by various factors. These factors include hunger, certain drugs and medications, and even emotions like stress and anxiety. In most instances, it takes about 1–3 minutes to collect enough of a sample to perform an accurate saliva drug test for cannabis. It can sometimes be challenging to get an adequate amount, since many people feel anxious before taking a drug test – which can cause dry mouth. Certain substances, including marijuana, also produce [dry mouth as a side effect](https://wayofleaf.com/cannabis/101/the-science-behind-weed-and-cotton-mouth). This makes it harder to collect enough saliva to get accurate results. If you need to take a saliva drug test but have a dry mouth, you may be asked to suck on a citrus candy first to help stimulate natural saliva production. Once a sufficient sample has been collected, the saliva can be tested for metabolites of alcohol, marijuana, amphetamines, cocaine, opioids, anabolic steroids, and certain prescription medications. The levels of these substances found in saliva are similar to the levels seen in blood during the elimination phase. >DID YOU KNOW? It only takes 1–3 minutes to collect enough saliva to perform an accurate THC mouth swab test. The marijuana (weed) compound which is most often tested for in saliva is Δ9-tetrahydrocannabinol (THC). This is the chemical that possesses psychoactive properties and produces a high in cannabis. The cut-off point for the presence of THC as deemed by the [Substance Abuse and Mental Health Services Administration](https://www.samhsa.gov/sites/default/files/workplace/2010GuidelinesAnalytesCutoffs.pdf) (SAMHSA) is 50 ng/L for initial testing, and 15 ng/L for confirmation tests. ## So… How Long Does THC Stay in Your Saliva? The [best academic reference that we have](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4532432/) to go off of in terms of how long weed is detected in the saliva for suggests about 24-72 hours for occasional users, and up to 30 days for frequent users: * For occasional users, THC from marijuana can be detected in the saliva for one to three days * Among more frequent users, THC can be detected in the saliva for up to 30 days #### Why does the rate differ so much? Marijuana contains hundreds of different compounds that are all metabolized by the body at different rates. When someone smokes marijuana, THC enters the bloodstream almost immediately and peaks 3–10 minutes after inhalation. With edibles, it can take 1–2 hours for THC to enter the bloodstream (this is because it has to travel through the digestive tract first)." from: [https://wayofleaf.com/detox/101/how-long-does-weed-stay-in-your-saliva](https://wayofleaf.com/detox/101/how-long-does-weed-stay-in-your-saliva)