You Might Not Overdose on Cannabis, But You Can Still Overdo It
Can you overdose on cannabis? This question is controversial, even among people who frequently use cannabis. Some people believe cannabis is as dangerous as opioids or stimulants, while others believe it’s completely harmless and has no side effects.
You can’t overdose on cannabis in the way that you can overdose on, say, opioids. To date, there have not been any reported deaths resulting solely from cannabis use, according to the Centers for Disease Control and Prevention (CDC) .
But that doesn’t mean you can’t overdo it or have a bad reaction to cannabis.
There isn’t a straightforward answer here because everybody’s different. Some people seem to tolerate cannabis well, while others don’t tolerate it well at all. Cannabis products also vary greatly in their potency.
Edibles, however, seem to be more likely to cause a negative reaction. This is partly because they take a long time to kick in.
After eating an edible, it can be anywhere from 20 minutes to 2 hours before you start to feel the effects. In the meantime, many people end up eating more because they mistakenly believe the edibles are weak.
Mixing cannabis with alcohol can also cause a negative reaction for some people.
Cannabis products containing high levels of tetrahydrocannabinol (THC), the chemical that makes you feel “high” or impaired, can also cause a bad reaction in some people, especially those who don’t use cannabis often.
Cannabis can have quite a few less-than-desirable side effects, including:
- thirstiness or a dry mouth (aka “cotton mouth”)
- concentration problems
- slower reaction times
- dry eyes
- fatigue or lethargy
- increased heart rate
- anxiety and other changes in mood
In rarer cases, it can also cause:
- paranoia and panic attacks
- nausea and vomiting
These side effects can last anywhere from 20 minutes to a full day. In general, cannabis that’s higher in THC is associated with more severe, long-lasting effects. And yes, it’s possible to wake up with a “weed hangover” the following day.
If you or a friend has overindulged, there are a few things you can do to reduce the unpleasant side effects.
If you’re feeling anxious, it’s good to self-soothe by telling yourself that you’ll be OK. Remind yourself that nobody has ever died from a cannabis overdose.
It might not feel like it right now, but these symptoms will pass.
If you’re feeling nauseated or shaky, try to have a snack. This might be the last thing you want to do, especially if you also have dry mouth, but it makes a big difference for some people.
Speaking of dry mouth, make sure you drink plenty of liquids. This is especially important if you’re vomiting, which can dehydrate you.
If you’re panicking, try slowly sipping water to help ground yourself.
Sleep it off
Sometimes, the best thing to do is wait for the effects to subside. Sleeping or resting is a good way to pass time while you wait for the cannabis to work its way out of your system.
If too much is happening around you, it can make you anxious and even paranoid.
Switch off the music or TV, leave the crowd, and try to relax in a calm environment, like an empty bedroom or bathroom.
Chew or sniff black peppercorns
Anecdotally, many people swear that black peppercorns can soothe the side effects of overindulging in cannabis, especially anxiety and paranoia.
According to research , black peppercorns contain caryophyllene, which might weaken the uncomfortable effects of THC. But this remedy hasn’t been rigorously studied, and there is no evidence in humans to support it.
Call a friend
It may be helpful to call a friend who has experience with cannabis. They may be able to talk you through the unpleasant experience and calm you down.
Having a bad reaction to cannabis usually isn’t a medical emergency.
However, if someone is experiencing hallucinations or signs of psychosis, it’s important to get emergency help.
Looking to avoid a bad reaction in the future?
Keep the following in mind:
- Start with low doses. If it’s your first time using cannabis, it’s a good idea start low and slow. Consume a small amount and give it plenty of time to kick in before using more.
- Be careful with edibles. Edibles take anywhere from 20 minutes up to 2 hours to kick in because they need to be digested first. If you’re trying edibles for the first time, or if you’re not sure of the strength, have a very small amount and wait at least 2 hours before having more.
- Try a low-THC cannabis product. Most dispensaries and cannabis shops list the amount of THC in their products. If you’re new to cannabis, or if you’re sensitive to the side effects, try a low-THC product or one with a high CBD:THC ratio.
- Avoid overwhelming situations. If cannabis sometimes makes you anxious or confused, it might be best to use it in a safe, calm environment.
While nobody has died from overdosing on cannabis alone, it’s possible to consume too much and have a bad reaction. This tends to happen more with edibles and high-THC products.
If you’re new to cannabis, pay careful attention to how much cannabis you’re consuming at a time and give yourself plenty of time to feel the effects before using more.
Sian Ferguson is a freelance writer and editor based in Cape Town, South Africa. Her writing covers issues relating to social justice, cannabis, and health. You can reach out to her on Twitter.
Some people insist it's impossible to overdose on marijuana, while others swear that they have. As with most debates like this, the truth lies somewhere in the middle.
The Harvard Gazette
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What we know and don’t know about pot
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By Alvin Powell Harvard Staff Writer
Date February 24, 2020
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The legalization of marijuana has spread around the country in recent years. Currently 33 states allow it for medical use and 11 for recreational. Yet scientists and researchers say a paradox about it endures: There has been broad public experience with pot, but the medical community still doesn’t know enough about the health effects — and what it does know is often obscured by enduring myths. Kevin Hill, associate professor of psychiatry at Harvard Medical School and director of the Division of Addiction Psychiatry at Beth Israel Deaconess Medical Center, has conducted marijuana-related research and is the author of the 2015 book “Marijuana: The Unbiased Truth about the World’s Most Popular Weed.” He is also co-chair of the National Football League’s Pain Management Committee, which is evaluating a possible role for cannabinoids in treatment. The Gazette spoke with Hill about where we are now in understanding the drug’s pluses and minuses.
GAZETTE: Marijuana legalization has swept the country over the last couple of years. What do we know now about its health effects that we didn’t know before?
HILL: We know a lot more about both the benefits and the risks of cannabis use, although I would say that the rate and scale of research has not kept pace with the interest. There is a growing body of literature on the therapeutic use of cannabis and, similarly, we’re learning bits and pieces about the problems associated with cannabis use. But our increased knowledge pales in comparison to the intense public interest, so one of the issues we often encounter is a growing divide between what the science says and what public perception is.
“There are a lot of things we don’t know, and a lot of answers we wouldn’t have expected” says Kevin Hill, who has conducted marijuana-related research and is the author of “Marijuana: The Unbiased Truth about the World’s Most Popular Weed.”
Jon Chase/Harvard Staff Photographer
GAZETTE: Is it that there are myths that haven’t been dispelled yet, either by widespread experience or by scientific findings?
HILL: The myths have been disproven. Unfortunately, the loudest voices in the cannabis debate often are people who have political or financial skin in the game, and the two sides are entrenched. Pro-cannabis people will say that cannabis is the greatest medication ever, and harmless. Others — often in the same field that I’m in, people who treat patients, people who do research with cannabis — will at times misrepresent the facts as well. They will go into a room of 100 or 200 high schoolers and relay the message that cannabis is as dangerous as fentanyl. That’s not true either. These camps seem to feel that even a single shred of evidence that runs counter to their narrative hurts them. So at the end of the day, a lot of what people hear about cannabis is either incomplete or flat-out wrong because both sides are promoting polar opposite views of cannabis.
GAZETTE: What is an example of these myths?
HILL: I think the greatest example is when you talk about the addictive nature of cannabis. You can become addicted to cannabis, though most people don’t. Yet invariably, when people hear about what I do, they say, “Oh, you’re an addiction psychiatrist? Well, cannabis is not physically addictive; it’s psychological.” So there are fallacies about cannabis. And they continue because people are invested in trying to get people to vote one way or another on issues like medical cannabis or legalization of recreational cannabis. That is a major problem. Every single day we have patients come in who are interested in using cannabis as a medication or they’re using it recreationally or are interested in cannabidiol, and they have beliefs about cannabis that they’ve held for years that aren’t true. And that becomes a major barrier. It’s hard to dispel those beliefs in the office.
GAZETTE: What is cannabis addiction like?
HILL: It’s less addictive than alcohol, less addictive than opioids, but just because it’s less addictive doesn’t mean that it’s not addictive. There’s a subset of people — whom I treat frequently — who are using cannabis to the detriment of work, school, and relationships. It’s hard for the majority of people — who may use once a month or once every six months, or they tried it in Vegas because it’s legal there — to recognize the reality that there are many people who are using and losing in key areas of their lives. I’ve had patients who have lost multimillion-dollar careers. It’s hard for people to understand that that can happen. I often compare cannabis to alcohol. They’re very similar in that most people who use never need to see somebody like me. But the difference is that we all recognize the dangers of alcohol. If you go into a room of 200 high school kids, they know it’s dangerous and binge drinking among high schoolers is way down. But if you ask that same group about cannabis, you’re going to get all different answers. Data that suggests that although cannabis use among young people is flat — that’s another misrepresentation, that it’s going up — the perception of risk among those young people is going down. So, while everyone’s talking about it, and stores are opening in Brookline, in Leicester, and all over the state, adults and young people are not clear about the risks.
GAZETTE: What about the other side, myths about cannabis’ harms?
HILL: How are things misrepresented by anti-cannabis crusaders? They tend to ignore the idea that dose matters. When we talk about the harms of cannabis, young people using regularly can have cognitive problems, up to an eight-point loss of IQ over time. It can worsen depression. It can worsen anxiety. But all of those consequences depend upon the dose. The data that shows those impacts look at young people who are using pretty much every day. They’re heavy users who usually meet criteria for cannabis-use disorder. So when people who are opposed to cannabis talk about those harms, they don’t mention that they’re talking about heavy users. The 16-year-old kid who uses once or twice a week, I’d still be worried about it, but that use has not been correlated to these harms.
GAZETTE: What constitutes heavy use?
HILL: Cannabis is different than alcohol, because with alcohol, you can use once a week, three times a week, and it can be a problem. You can have eight drinks once a week and get into a whole bunch of trouble. Cannabis is a little different in the sense that the people who run into trouble are using it pretty much every day, multiple times a day for the most part. That’s how this less-harmful, less-addictive substance turns into something that’s very harmful for them.
GAZETTE: Are the characteristics of cannabis addiction common to other types of addiction?
HILL: They are. When someone’s sitting in my office, if you redacted some of the details of their story, it’d be hard to tell who’s got which problem: alcohol versus opioids versus cannabis. The onset — what will bring you into my office — is different. People who are using cannabis are not going to knock off a CVS to fuel their habit. If somebody’s using fentanyl, they may overdose and that could be potentially fatal. That’s not going to happen with cannabis. But when you talk to them, other details are often the same. “My wife said I gotta come talk to you or she’s gonna kick me out.” And that can happen to somebody who’s drinking, that could happen to somebody using opioids. It’s not as dramatic if cannabis is the drug of choice, but once somebody meets the criteria for a cannabis-use disorder or alcohol-use disorder or opioid-use disorder, there are a lot of similarities, more similarities than differences, frankly. One unique thing about cannabis is that on the same day, I may have somebody who is 26, smoking four times a day, graduated from a local elite university, and not making it like they want to be making it. Then, the next hour, I may see a 70-year-old woman who has chronic back issues and tried multiple medications, multiple injections, and wants to use cannabis for her pain. There aren’t a lot of doctors who see both of these patients and that is one of the reasons why people take really strong positions, when in fact many of the answers on cannabis are down the middle. There are a lot of things we don’t know, and a lot of answers we wouldn’t have expected. I’ve done studies myself where I hypothesized one thing, and something else comes out. Are you going to dismiss that or let that new information shape what you think about cannabis? You have to be open-minded in an area that is continuing to evolve. If you aren’t open-minded and willing to have a sensible conversation about cannabis, you won’t be able to reach your patients. A lot of times patients don’t tell their primary care doctor about their cannabis use, their use of CBD, because they think their physician won’t approve of their use. That’s another major problem. If you’re using CBD to treat a given medical condition and your doctor doesn’t know it and you’ve got six other medications, that could be a major issue.
GAZETTE: We’ve talked about negatives. What is the truth of the positive health benefits?
HILL: We’re conditioned as physicians to believe that cannabis is bad for you, but there is data that it can be useful in certain cases. I would prefer that we use FDA-approved medications when possible. They are much safer, and you can be sure of the purity and potency. But there is evidence to support the use of cannabis and cannabinoids for a handful of medical conditions. That is dwarfed by the number of conditions for which people are actually using it, but the evidence of benefit is not zero. To a lot of doctors, it’d be convenient if it was zero so they could tell patients that this whole idea is a sham. Thus, there are physicians who aren’t willing to entertain data demonstrating therapeutic use of cannabis. I think that’s a missed opportunity because if a patient comes in and says, “I want to use cannabis to treat condition x,” cannabis might not be the best treatment for that condition, but just being willing to engage in a conversation about it, you may get them into treatment they might not otherwise get into. If they said, “Look, I want to use cannabis to treat my anxiety,” I’m not going to recommend using whole-plant cannabis to treat anxiety, but maybe they haven’t tried cognitive behavioral therapy. Just by having that conversation, you could do a lot of good.
GAZETTE: Is pain one area that cannabis is proven for?
HILL: In 2015, we had two FDA-approved cannabinoids, dronabinol and nabilone, for nausea and vomiting associated with cancer chemotherapy, and for appetite stimulation in wasting conditions. Last year they added cannabidiol — only one version is FDA-approved — and it is for a couple of pediatric epilepsy conditions. Beyond the FDA-approved indications, the best evidence is for three things: chronic pain, neuropathic pain — which is a burning sensation in your nerves — and muscle spasticity associated with multiple sclerosis. There are more than six randomized control trials for each of those three conditions. There are problems associated with some of those trials — sample sizes are small and the follow-up periods are not as long as we would like them to be. I wish there was better evidence for chronic pain, but as long as we have a clear conversation about what the risks may be, then to me, there’s enough evidence for those three things to think about cannabis or cannabinoids not as first-line or second-line treatments but as third-line treatments.
With legal marijuana easier to find, a Harvard professor addresses myths and progress finding answers about pot’s health impacts.