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Anyone who’s had cannabis is familiar with the red eyes that follow. This redness may be slight or extremely pronounced, depending on how much weed you consumed and other factors. But why does weed make your eyes red? What exactly is it about cannabis that turns your peepers all bloodshot?
Read on for answers to these questions and to learn if weed red eye is dangerous and preventable.
Why Does Weed Make Your Eyes Red?
Weed contains THC, which relaxes your eyes’ blood vessels and causes more blood to flow into them, turning your eyes red. The blood-filled vessels are what turn your eyes red and bloodshot. This process is called vasodilation.
Another THC effect that causes eye redness is the cannabinoid lowers blood pressure. Low blood pressure causes vasodilation as your body tries to pump more blood to your organs, including your eyes. This increased ocular blood flow, as we’ve pointed out, leads to bloodshot eyes.
Lastly, if you’re smoking weed, the fumes can irritate your eyes and worsen their redness. Then there’s dehydration from cannabis consumption, which can worsen red eyes. How? Dehydration means your body’s moisture level is low. Since your eyes require moisture for protection and lubrication, dehydration can cause irritated and inflamed eyes.
In summary, weed makes your eyes red because THC increases blood flow to your eyes, making your eyeballs’ many blood vessels more visible. It doesn’t matter if you get high by smoking, vaping, eating, drinking, or inserting a cannabis suppository. As long as a cannabis product contains at least 5% THC, you’ll likely get red eyes.
How Long Do Red Eyes from Weed Last?
Eye redness or high eyes from weed can last from 1-4 hours depending on how much cannabis you had and the strain’s THC potency. The higher the THC level, the more pronounced the red eyes will be, leading to more intense and longer-lasting redness.
Also, your metabolism will determine the duration of eye redness from weed. For example, if you have a fast metabolism, THC’s effects on your body will fade faster, causing eye redness to fade just as quickly. The opposite will occur if your metabolism is slow.
Lastly, how you consume cannabis will also affect how long your eyes stay red after taking weed. Consumption methods that cause THC to stay in your system longer will prolong red eyes from vasodilation. For instance, edibles like gummies have a slow onset as your body gradually digests them and releases THC into your blood. This slow release contributes to eye redness continuing for as long as your body digests the edible and keeps releasing THC.
Does How You Consume Weed Affect Red Eye?
Yes, red eye intensity and duration depend on how you consume weed and the type of cannabis product you consume. Higher THC weed strains or cannabis products, like THC diamonds, cause more pronounced eye redness because vasodilation will be more intense.
Also, eye redness from smoking and vaping weed may end quicker because THC effects are felt faster but don’t last very long with these consumption methods. In contrast, if you ingest cannabis as an edible, oil, or supplement, the THC effect will last longer, causing eye redness to persist for just as long. This is because digesting cannabis products is slow and gradually releases THC into your bloodstream.
Weed Making Your Eyes Red Isn’t Always Bad
Besides making it seem like you have a glaring case of pinkeye, red eyes from weed aren’t always bad. The redder your eyes, the more potent the weed likely was, so you know for sure you got a good batch. Also, red eyes signify that whatever cannabis product you took is working, even if you don’t feel high yet.
If you have glaucoma, THC’s effect on the eyes can be a huge benefit. Glaucoma damages optic nerves by causing high pressure inside the eyes. Untreated, it can lead to vision loss and pain. THC treats glaucoma by triggering vasodilation, expanding blood vessels to reduce pressure within the eyes (intraocular pressure).
How to Get Rid of Red Eyes from Weed
While red eyes from using cannabis aren’t avoidable, there are some things you can do to minimize the redness. Firstly, use over-the-counter eye drops, specifically eye drops for redness relief, like Visine or Clear Eyes. These OTC eye drops can reduce eye redness within minutes by constricting ocular blood vessels, counteracting THC’s blood vessel widening effect.
Secondly, staying hydrated while using weed prevents dehydration, which can make your eyes redder. Hydrate with water rather than dehydrating drinks like coffee or alcohol. Besides minimizing eye redness, staying hydrated will also reduce cotton mouth, which is another side effect of weed use.
Other measures you can take to reduce weed making your eyes red include putting a cold compress over your reddened eyes and taking less potent cannabis. A cold compress’s coolness can help reduce cannabis-induced eye redness or swelling. Less potent strains or cannabis products, on the other hand, will minimize eye redness since higher THC levels cause more bloodshot eyes.
Factors Influencing Eye Redness from Weed
Yes, your eyes will get red if you consume cannabis or any product with significant THC content. However, several factors determine how red your eyes will get and how long the redness will last. These factors include:
- THC Concentration: The higher the THC content, the higher the intensity and duration of eye redness will be. For example, eye redness from smoking skunk weed will be far more pronounced than redness from low-THC strains like Suzy Q or ACDC. As such, you should consume products with lower THC levels if you would like to minimize eye redness.
- Method of Consumption: Red eyes typically appear quickly after smoking due to the rapid absorption of THC into the bloodstream. Similar to smoking, vaping also leads to a quick onset of red eyes as THC enters the bloodstream rapidly. In contrast, red eyes from edibles occur slower than when smoking or vaping cannabis. However, the duration may be longer since the effects of edibles can last several hours. So, if you vape live rosin, live resin or distillate carts, eye redness will appear faster but won’t last as long as eating THC gummies.
- Individual Physiological Differences: Since we’re all built different, THC’s effect on you may be different from its effects on me. For instance, women generally experience stronger or longer-lasting THC effects than males. Also, heavier individuals may feel slower onset but longer-lasting effects than smaller people.
- Irritation from Smoke or Vapor: Smoking weed can generate harsh fumes that irritate your nose and eyes, leading to red and watering eyes. In contrast, vaping rarely irritates the eyes and nose, preventing ocular irritation that worsens eye redness. So, vaping is better than smoking for less eye irritation.
Common Myths About Red Eyes and Weed
Myth 1: It’s Caused by Smoke
Many people think red eyes from weed is caused solely by smoke, but that’s not the full story. The redness actually comes from THC, the psychoactive compound in cannabis. THC makes blood vessels in the eyes expand, filling them with blood and causing that signature redness. So, whether you smoke, vape, or ingest weed, THC is the culprit that causes red eyes, not just the exposure to smoke.
Myth 2: Everyone Gets Red Eyes
Not everyone will experience red eyes after using weed. Some individuals have blood vessels that don’t dilate as much in response to THC, leading to less noticeable red eyes. Also, individuals with a higher THC tolerance may experience less pronounced effects, including eye redness. It’s all about individual differences—so if you don’t get bloodshot eyes from weed, you’re not ALIEN!
When to Be Concerned About Red Eyes
Red eyes should be a common and harmless side effect of consuming weed, but there are times when you should pay closer attention.
- If Redness Persists for More Than 24 Hours, especially after the effects of THC have worn off, it could indicate an underlying issue like an eye infection or allergic reaction.
- If You Experience Pain or Discomfort, such as throbbing or a gritty feeling, it may be a sign of something more serious, such as an eye injury, infection, or dry eye condition.
- If Vision Is Affected, such as difficulty seeing clearly or sensitivity to light (photophobia), it could be a sign of an eye condition that needs medical attention.
- If You Have Red Eyes Combined With Symptoms Like Swelling, Drainage, Or Headaches, it might suggest an infection or allergy rather than just the effects of weed.
While allergic reactions to cannabis are rare, they do happen. The allergy may affect the skin, respiratory system, or eyes. Skin reactions may include itching or rashes, while respiratory symptoms may be sneezing, wheezing, or shortness of breath.
Eye irritation or conjunctivitis is another uncommon reaction, sometimes caused by cannabinoids or terpenes. In extremely rare cases, anaphylaxis, a severe allergic reaction involving difficulty breathing and swelling of the throat may occur. If you experience an allergic reaction to cannabis, immediately stop use and seek medical attention.
Conclusion
If you consume cannabis with significant THC levels, you’ll likely get red eyes. THC expands blood vessels in the eyes, increasing blood flow through them. These expanded blood-filled vessels against the backdrop of your white eyeballs are what make your eyes appear bloodshot after weed use.
For less red eyes after consuming cannabis, you can use low-THC weed strains or eye drops for red eye relief. Or who knows? You might be one of the lucky few who don’t get red eyes after using weed. If you’re, let us know how it feels to be special in the comments.
FAQs about Why Does Weed Make Your Eyes Red
Why does weed make my eyes red?
Weed contains THC, which increases blood flow to your eyes, turning them bloodshot. The redness is from engorged blood vessels standing out against the whites of your eyes.
Does everyone get red eyes from weed?
No, a few people don’t get red eyes from weed. This includes individuals with a higher THC tolerance and people who consume lower-THC products.
Are red eyes harmful?
No, red eyes from weed isn’t harmful. However, if cannabis-induced red eyes last longer than a few hours or you experience eye discomfort, excessive discharge, or impaired vision, seek medical attention.
Can weed cause dilated pupils?
Yes, weed can cause dilated pupils in some cases, although this effect is less common and not as prominent as other symptoms like red eyes. The effect is usually short-term and might make your eyes more sensitive to light while you’re high.
Can CBD cause red eyes too?
No, CBD doesn’t usually cause red eyes. Unlike THC, CBD doesn’t lower blood pressure or dilate blood vessels in the eyes. If eye redness occurs, it’s likely due to other factors like smoke or an allergic reaction, not CBD itself. Or, perhaps the product contains more THC than advertised.
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