Marijuana Overdose: Can You Get Poisoning from Smoking Too Much?

Government statistics show that in 2017, approximately 14,000 Americans died from a cocaine overdose. About 10,000 died from an overdose of psychostimulants like meth or prescription drugs like Ritalin or Adderall. Nearly 50,000 died from opioid overdoses.

Not a single person, though, died in 2017 from smoking or ingesting too much marijuana. In fact, there’s not a single fatality attributed directly to pot – in history.

And those numbers are totally consistent with research that’s regularly done by scientists.

What Would Theoretically Be A Lethal Dose Of Weed?

Scientists have determined how much of every drug, including recreational drugs, would have to be consumed in order to cause death; the way they explain it, they calculate the potential for short-term fatal toxicity. The results are expressed in something called the LD-50, representing a lethal dose for 50% of the test subjects. (Remember, these tests are done on animals, so the results have to be taken with a grain of salt. No, not bath salt.)

Without getting into confusing numbers, the findings show that a potentially lethal dose of heroin or GHB is actually a lot lower than the amount you’d need to get high. However, you’d have to take ten or twenty times the “effective dose” of alcohol, coke or ecstasy to have a 50% chance of death, according to these animal studies; for mescaline and roofies, it would require twenty to eighty times the “effective dose” to have a 50% chance of dying.

What about pot? The number is so low that it can’t be measured. When pressed, scientists who calculate LD-50s guess that risking a 50% chance of a deadly overdose would require consuming 100 to 1000 times the amount it would take to get baked. (Our term, not theirs. They use more scientific language.)

Other and more recent ways to measure the potentially deadly effects of a drug involve complicated formulas that include the LD-50. But the end result of the calculations is something called the “therapeutic index,” and initial research on the “TI” shows that the LD-50 numbers are actually quite low.

Marijuana is said to have a therapeutic index of 40,000 to 1 (by comparison, morphine’s TI is 70:1). Here’s what that means: you’d have to consume 40,000 times the “effective” dose of weed before running a significant risk of death. Put another way, you’d have to smoke somewhere between 25,000 and 40,000 joints – or consume 1500 pounds of pot – in 15 minutes. If you want to put that into even greater perspective, the equivalent risk numbers are 1.2 grams of coke and 80mg of Oxy.

That’s a long-winded way of confirming what every stoner and the recreational user already knows – you can’t overdose on weed.

But not everyone equates “overdose” with “death.” Some medical professionals, not to mention those opposed to legalization, define an overdose as experiencing serious, non-fatal medical issues after overindulging. And that certainly can happen.

The Risks of Overdoing It

Regular tokers probably know someone – or at least have heard stories about someone who knows someone – who had a really bad reaction after smoking too much weed.

The ones that most readers can likely relate to are hallucinations and paranoia, which taken to an extreme level can lead to psychotic episodes. The medical cases which have been reported usually involve people already prone to those disturbing health episodes, since they can continue for much longer than the amount of time that THC is active in the body.

Other serious incidents reported having been triggered by “THC toxicity” include a period of vomiting which can’t be controlled (but can often be stopped by taking a hot shower) and heart palpitations or arrhythmias.

However, documented incidences of those issues don’t clarify whether the patients also had alcohol or other drugs in their system. And mixing intoxicants to excess is much more likely to bring about serious medical problems, than simply smoking enough herb to get totally wasted.

The bottom line? A very small number of people who smoke too much, do too many dabs, or consume too many edibles do end up needing emergency room treatment. But even then – they’re not going to die of an overdose. It simply doesn’t happen.