May 9, 2023

Does THC Make Your Eyes Red?

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Key Takeaways

Cannabis causes red eyes because THC binds to cannabinoid receptors, widening blood vessels and increasing blood flow, which leads to redness and irritation in the eyes.
To prevent or reduce red eyes after consuming cannabis, effective methods include using eye drops, applying a cold compress, staying hydrated by drinking water, or simply waiting for the effect to subside naturally.
Red eyes are a common but not universal side effect of cannabis, and planning consumption for the evening or using remedies can help manage the appearance until the redness resolves on its own.

There’s nothing better than enjoying cannabis on a Saturday night, but let’s be honest—sometimes we don’t wait for the evening and notice some... interesting effects later in the day. But whatever time of day it is, no one wants to be left with the scent that this fascinating plant can leave behind.

You likely change your clothes, take a shower, or chew some gum to deal with the aroma of cannabis, but sometimes we forget about our eyes.

Yes, according to numerous consumers and studies, THC can make your eyes red.

Calm down- you may not ever experience red eyes after a smoking session, but this effect is common. It all depends on how your unique endocannabinoid system processes THC. But if you’re not a fan of looking like you didn’t get a good night’s sleep, use the techniques below to prevent your eyes from turning red in the first place.

But first, let’s find out what causes it.

Why Does Cannabis Cause Red Eyes?

Looking in the mirror a few minutes after you smoked, you may have noticed that your eyes are red and glossy. It’s common to assume that it is irritation from the smoke, and while this may be the case for some individuals, smoke isn’t the only contributing factor.

To grasp why Delta-8 THC or Delta-9 THC really causes red eyes, let’s review how cannabinoids affect the human body. Nearly every animal, including humans, has an endocannabinoid system (ECS). This vast network of chemical messengers and receptors influences and regulates our internal biological functions, such as pain perception, reproduction, sleep, and appetite.

To ensure a state of internal balance- or homeostasis- the human body naturally produces compounds called “endocannabinoids” to send signals throughout. One of the endocannabinoids responsible for modulating our brain's reward system is called “anandamide.” Anandamide has a similar structure to THC, which is what allows this "phytocannabinoid" to interact with the ECS (CB1 and CB2 receptors).

As THC binds to cannabinoid receptors, it widens the blood vessels, increasing blood flow, and hence decreasing blood pressure. When this happens, the increase in blood flow will cause your eyeball to appear irritated and red.

Ways to Prevent Your Eyes from Getting Red

So, what should you do to prevent getting red eyes after smoking?

The truth of the matter is that no matter how you consume cannabis, whether or not it's smoking, cannabinoids are going to have varying effects. Of course, some of these effects are pleasurable, like euphoria and relaxation, whereas others are not so glamorous, like red eyes.

Effects from THC usually take a few hours to subside on their own. But you may not have the time to wait for your eyes to look less red. So, we have a couple of tips to help combat this common occurrence.

1. Use Eye Drops

If your first instinct is to use eye drops, you are right on target. Eye drops are essential if you have plans after your session with cannabis. You can purchase eye drops at your local pharmacy or grocery store.

Simply take a drop or two before and after you consume cannabis, and watch it quickly soothe your eyes. After a few minutes, you can confidently enter a room knowing your eyes are crystal clear... or, at least better than without them.

NOTE: For those who wear eye makeup, try using eye drops before applying any eye makeup to avoid smudging your mascara or other cosmetics.

2. Use An Ice Pack

Cold compresses are used as a home remedy to treat various eye problems. This is because cold temperatures can reduce inflammation and redness by constricting the blood vessels around the eye.

Using something cold will minimize the redness and make your eyes less noticeable.

So grab an ice pack, a cold, wet towel, or a bag of frozen vegetables and hold it against them for up to 10 minutes.

3. Drink Water

woman taking a drink of water from a glass

Water may not be your drink of choice, but dehydration will only worsen eye redness and cause other health issues.

To ensure you stay hydrated, steer clear of alcohol and excessive caffeine. And before consuming cannabis, drink plenty of water, as this may help prevent red eyes and even dry mouth.

4. Wait it Out

Although we have given you many tools to work with, there is a possibility that you don’t have eye drops or a cold compress.

With this in mind, your options are limited, so you can always put on some sunglasses or act like you are dealing with allergies. Sure, it isn’t the ideal route, but it may give you some time until your eyes resolve on their own.

Of course, our recommendation is to plan your session for the evening or the weekend so you can unwind without worrying about red eyes. But if you're in a pickle, just wait it out and be patient. This effect will pass!

Final Thoughts

Red eyes are just one of the many common effects some (but not all) cannabis consumers experience. Using the techniques above and a bit of planning can help manage some of the redness.

Until next time, happy exploring, and mind your mind.

FDA Disclaimer: The statements made regarding these products have not been evaluated by the Food and Drug Administration. The efficacy of these products has not been confirmed by FDA-approved research. These products are not intended to diagnose, treat, cure, or prevent any disease. All information presented here is not meant as a substitute for or alternative to information from health care practitioners. Please consult your healthcare professional about potential interactions or other possible complications before using any product. The Federal Food, Drug, and Cosmetic Act requires this notice.

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