Why Does Weed Give You Cottonmouth? The Science of Dry Mouth and 6 Fixes

Smoking weed flower gives you cottonmouth because THC binds to cannabinoid receptors in your salivary glands and tells them to slow down, so less saliva makes it into your mouth. It's harmless and temporary, but knowing how it works helps you understand what weed does to your mouth, from that classic dry feeling to possible long-term effects on oral health.

Whether you're a regular smoker or thinking about trying it for the first time, here's what you need to know about how cannabis affects your mouth.

How is saliva made?

Making saliva is a complex process with several stages and components. Broadly speaking, it happens in two main phases. First, specialized cells called acinar cells secrete a fluid that's similar in composition to blood plasma.

That initial fluid then travels through the salivary ducts, where its makeup changes: sodium and chloride are pulled out, and potassium and bicarbonate are added. The end result is a “hypotonic solution” (more dilute than your blood) that's released into the mouth.

How your nervous system controls saliva

Saliva secretion is regulated mainly by the parasympathetic nervous system (PNS), the “rest and digest” branch that plays a key role in digestion and in getting ready to eat. The PNS switches on receptors in the salivary glands through nerve signals carried by the chorda tympani nerve.

This nerve, a branch of the facial nerve, connects with the submandibular ganglion (a cluster of nerve cells next to the submandibular gland) and releases acetylcholine, the key messenger that kicks saliva production into gear.

On top of acetylcholine, norepinephrine also plays a part. It's released by sympathetic nerve fibers and acts directly on the myoepithelial cells that wrap around the acinar cells. Norepinephrine makes those myoepithelial cells contract, which helps squeeze the saliva out.

Why does weed make your mouth dry?

The endocannabinoid system (ECS) plays a major role in regulating all kinds of body functions, saliva production included. It includes the CB1 and CB2 cannabinoid receptors, which are found all over the body, salivary glands included.

When cannabinoids interact with these receptors, they can seriously cut down saliva production, which leads to that familiar cottonmouth feeling when you use cannabis.

How the endocannabinoid system affects saliva production

Scientific research has linked the endocannabinoid system to the drop in salivation that comes with using cannabis. A study published in Scientific Reports found that activating CB1 receptors in the salivary glands blocks the release of neurotransmitters that are essential for making saliva.

Without the right “signal” to start the process, the glands produce less saliva, and you end up with a dry mouth.

Another study, published in the International Journal of Molecular Sciences, looked at how cannabinoids affect the epithelial cells of the salivary glands. The results showed that THC, the best-known cannabinoid, lowers the secretory activity of those cells, cutting saliva production even further.

Cannabis and blood flow: the vasodilation angle

Beyond its direct effects on the salivary glands, cannabis also dilates blood vessels, which may contribute to lower saliva production. Cannabinoid-driven vasodilation could change the blood supply to the salivary glands and get in the way of their ability to secrete saliva efficiently.

Is cottonmouth from weed something to worry about?

The good news: dry mouth from smoking weed isn't serious and doesn't last long. There are simple ways to ease the discomfort and shorten how long it hangs around. Staying hydrated, using oral moisturizing products and rinsing your mouth can all help.

Bottom line: weed can dry out your mouth because cannabinoids interact with the endocannabinoid system, which controls saliva production. But there are practical ways to manage it and keep this side effect to a minimum.

How to get rid of cottonmouth after smoking weed

A dry mouth and throat is one of the classic side effects of weed, and it can show up even with a moderate amount. During heavier sessions, though, it can ramp up and get pretty uncomfortable. Luckily, there are a few solid ways to fight cottonmouth and stay comfortable.

1. Stay hydrated

Hydration is one of the most effective ways to beat dry mouth. Sipping water regularly helps take the edge off and keeps your mouth moist. Keeping a water bottle handy during or after a session is a no-brainer.

2. Chew gum

Chewing gum is a simple fix for cottonmouth. The act of chewing stimulates your salivary glands, which gets saliva flowing and eases the dryness.

3. Suck on ice cubes or lollipops

Sucking on ice cubes or lollipops can help get the saliva going. Ice cubes have the added bonus of cooling down your mouth and throat.

4. Eat foods you have to chew

Foods that take some serious chewing, like dried fruit or beef jerky, can help stimulate the salivary glands and boost saliva production. They work, and they're a tasty way to fight dry mouth (and the munchies while you're at it).

5. Use oral moisturizing products

For more complete relief, try products made specifically to moisturize the mouth. They coat the mucous membranes with a moist film that helps ease the dryness. Plenty of prescription drugs also cause dry mouth, so there's a wide range of products out there to deal with it.

6. Hope from future research

Ongoing research into the endocannabinoid system and how it shapes salivation could lead to products designed specifically to counter xerostomia (the medical term for dry mouth). They wouldn't just help people who overdo it with cannabis, but also people with medical conditions or on medications that cause persistent dry mouth.