Why does weed make your eyes red? It’s the eternal question of every single teenager just before they face their parents after smoking a joint. It’s also a question posed by any student or employee returning to work after a quick lunch session. Red eyes are a dead giveaway after smoking weed. Blood shot eyes always strike at the most inopportune times.

Even if you smoke weed on a daily basis, and develop a solid tolerance, you can’t avoid red eyes. No matter if you are just feeling a little buzzed or totally floored after blazing, red eyes can technically hit at any time. Bloodshot eyes don’t just happen to smokers either; they are also a side effect from edibles. Some people are unfortunately more susceptible than others.

So, Why Does Weed Make Your Eyes Red?

Although there are many different known cannabinoids found in weed, there is only one culprit behind bloodshot eyes: THC. Tetrahydrocannabinol is the dominant cannabinoid in most strains of marijuana, and the sole cannabinoid responsible for getting you stoned. While many other cannabinoids are making their way into the dispensary, their purpose is strictly medicinal. Only THC will get you high.

One of the side effects of THC is the sensation of dry mouth; another is a drop in blood pressure. If you’ve ever gotten light headed after puffing, its a good demonstration of just how quickly THC can lower your blood pressure. In most circumstances, it’s not dangerous, but it does affect the blood cells in your eyeballs.

Your body is well adapted to make internal adjustments in response to minor stressors. One perfect example is the way the blood vessels in your eyes expand in response to low blood pressure. It’s all to maintain enough pressure within the eyeball for proper vision.

The dilated capillaries and opened blood vessels welcome more blood flow into the area, and the eyeballs start to appear red and bloodshot. In comparison to other areas of the body, the blood flow also more visible against the whites of your eyes.

Another exasperating cause of red eyes could be allergies. Not everyone will experience an allergic reaction to weed, but some people might find the smoke irritates their eyes. If your eyes feel itchy, especially dry or especially watery, that could be a telltale sign that you are also experiencing an allergic reaction. So not only are you fighting dilated blood vessels, but also a marijuana allergy!

How to Get Rid of Red Eyes

No matter which way you look at it, red eyes are an inevitable side effect of smoking weed. Because red eyes are an internal reaction to the cannabinoid THC, it’s not even possible to avoid through edibles. In fact, because edibles are usually more potent, your eyes might merely get redder. The higher the THC, the more at risk you are of bloodshot eyes.

There is some preliminary research into possible cures for dry mouth, but nobody has yet figured out how to cure red eyes. That said there are a few ways to avoid or at least reduce the appearance of red eyes after smoking or ingesting cannabis.

Eye Drops

Sold at drugstores and gas stations everywhere, eye drops are the go-to solution for stoners everywhere. Cheap, quick, and semi-effective, eye drops are one of the most popular ways to reduce the overall redness. They don’t treat the cause (dilated blood vessels), but they can at least help soothe dry or itchy eyes while the high lasts.

Low THC Strains

For anyone smoking weed for its medicinal purposes, it might be worthwhile to source another strain with lower THC levels. There is often a lot of overlap between the various cannabinoids, and another one might be equally as medicinally beneficial for your ailment. Obviously, if you are just smoking weed for the euphoric high, this solution isn’t going to work for you.

Schedule Accordingly

Anyone trying to avoid an awkward confrontation about their bloodshot eyes might just need to reschedule their smoking sessions. Don’t smoke right before work, if you expect your boss to grill you about your red eyes. Don’t eat an edible if your parents are coming home soon. Medicate with marijuana during your own time, where you can chill, relax, and not worry about the state of your eyeballs.

Allergy Medication

If you suspect you are fighting an allergic reaction to marijuana on top of the unavoidable THC reaction, try an antihistamine. Over the counter, allergy medications work great for reducing the dry, itchy sensation. Any heavy smokers might want to consider the long-term effects of antihistamines before popping them every day, but a casual smoker shouldn’t have any issues with taking one before a relaxed session.