While prescription painkillers cause thousands of overdose deaths each year, no one has ever died from a marijuana overdose.

But is it even possible to overdose on weed? The answer is no, according to the National Cancer Institute. And here's why:

"Because cannabinoid receptors, unlike opioid receptors, are not located in the brainstem areas controlling respiration, lethal overdoses from Cannabis and cannabinoids do not occur."

In other words, marijuana and opioids affect different pathways of the body. Opioid pathways, also known as receptors, are present in areas of the brain that control breathing. As a result, taking too many painkillers can cause a person to stop breathing.

But marijuana acts on a completely different set of pathways. These pathways are called cannabinoid receptors and they do not affect respiration. Thus, marijuana cannot cause someone to stop breathing, no matter how much they ingest.

Therapeutic Index

Another way of measuring a drug's safety is by its therapeutic index. The therapeutic index is the ratio between a drug's lethal dose and its therapeutic dose (amount that causes a therapeutic effect).

Studies show that marijuana has a therapeutic index of 40,000:1. This means someone would have to take 40,000 times the normal amount of marijuana in order to die.

Opioid-based painkillers have much lower therapeutic indexes. For example, the therapeutic index of morphine is only 70:1.

Taking Too Much

It may be impossible to die by marijuana overdose, but that doesn't mean you can't take too much of it.

As Dr. Sunil Aggarwal explains in the following video, large doses of marijuana can lead to negative symptoms, such as acute psychosis and paranoia.

This occurs more often in novice users who are unfamiliar with dosing. Taking marijuana orally also poses a greater risk, since the effects are delayed and thus harder to predict.

But with all that said, the negative symptoms of a marijuana overdose are only temporary and should wear off within 24 hours. Unlike other drugs, taking too much marijuana won't cost you your life.

Source: LeafScience