This Is Why Pot Makes Your Mouth So Dry

After the munchies, cotton mouth is probably one of the most well known side effects of using marijuana. But though it's incredibly common, not many people actually understand why cotton mouth happens — or why weed causes it.

Fortunately, a group of scientists from the University of Buenos Aires have figured out a scientific explanation for this phenomenon.

Essentially, cotton mouth is a result of THC’s interactions with the body’s endocannabinoid system. This system is involved in a number of bodily processes and is activated by cannabinoids found in marijuana.

As it turns out, researchers have discovered that both CB1 and CB2 cannabinoid receptors are present in the submandibular glands, which are a pair of glands beneath the floor of the mouth that are responsible for producing about 70% of our saliva.

THC, the main psychoactive ingredient in cannabis, is a powerful cannabinoid. And when it enters your body, it binds to cannabinoid receptors — including the ones in your mouth. That temporarily shuts down the lines of communication between the nervous system and the saliva-producing glands. It's this short-term shut-down that causes the body to reduce the amount of saliva it produces.

Before we learned about the endocannabinoid system and the presence of cannabinoid receptors in the mouth, many people assumed cotton mouth was the result of hot smoke drying out smokers’ mouths. But now researchers have discovered that it’s more about the chemical processes of THC interacting with the body and less about the actual smoke. That also explains why people can experience cotton mouth whether they smoke, vape, drink, or eat.

Saliva helps you eat and digest food, which means that cotton mouth can be a bit uncomfortable — especially when you also get the munchies. When that (sometimes awkward) combination strikes, try eating crushed ice or chewing gum to keep your mouth moist. That will make it even more enjoyable to satisfy your cravings for food.

A version of this article originally appeared on Green Rush Daily.

(Refinery29 in no way encourages illegal activity and would like to remind its readers that marijuana usage continues to be an offense under Federal Law, regardless of state marijuana laws. To learn more, click here.)