What causes weed eyes?

Red eyes from smoking are a staple of the stoner stereotype. But why the heck does cannabis make your eyes red? And what are the weed effects on eyes?

Weed eyes are caused by weed lowering your blood pressure and dilating your blood vessels and capillaries. The combination of lower blood pressure and dilation increases blood flow to your eyes and makes the whites appear red.

Marijuana eyes are more prevalent when you consume high-THC strains. Red eyes from weed can even last for several hours- so if you need to go to an important event and you’re prone to redness, plan accordingly!

Keep reading to learn everything you need to know about weed eyes!

Why does weed make your eyes red?

Weed makes your eyes red because marijuana dilates your blood vessels and capillaries. It also lowers your blood pressure.

By doing so, it effectively increases blood flow throughout the body- and your eyes are no exception! The excess blood shows through the whites of your eyes, making your eyes look red.

The higher the THC ratio in your weed, the stronger the possibility that you will have red eyes. The same can be said about a large smoke session. Basically, the more THC you consume, the more red your eyes can get.


Does weed make your eyes dry?

Weed makes your eyes dry, and there are even scientific studies to back it up!

Researchers looked into the physiological mechanism through which weed dries eyes. The study of weed eyes actually led to a large discovery regarding tear regulation that might be able to help those who suffer from chronic dry eyes!

To quote the weed eye study’s conclusion:

“Our results suggest a novel…physiologic basis for the dry eye symptoms experienced by cannais users: activation of neuronal CB1 receptors in the lacrimal gland reduces tearing.”

So there you have it. Weed makes your eyes dry, and we know why, and it even led to a step towards treating chronic dry eye syndrome. Not too shabby for a meager stoner stereotype!


Do edibles make your eyes red?

Edibles make your eyes red. Your eyes get red from THC content, not from the act of smoking itself. Sorry to be the bearer of bad news!

However, edibles don’t make your eyes red immediately the way smoking or vaping does. 

Your body takes longer to metabolize the THC in edibles than it does to metabolize THC when smoking or vaping.

Something else to note is that high-dose edibles can contain a LOT of THC. If you’re taking high-dose edibles, you’ve got a good shot at developing some intense red eyes. 

Meanwhile, if you’re just microdosing edibles throughout the day, you’re unlikely to develop red eyes because of how low the THC content is.

Does CBD make your eyes red?

CBD does not make your eyes red because CBD doesn’t lower blood pressure or dilate blood vessels and capillaries. And as you (should) know by now, those are the two reasons that THC makes your eyes red.

But it does easily get lumped into the overall cannabis stereotype by a large, uninformed portion of the general population. So it makes sense that people may assume that CBD makes your eyes red.

Does vaping make your eyes red?

Vaping makes your eyes red because THC content is responsible for making your eyes red, not the act of smoking dry herb itself. 

Pop quiz- what exactly does THC do to make your eyes red? Double check your answer in previous sections!

Vape pens vary greatly in THC content, but there are definitely some very high-dose vapes on the market. These THC-heavy vapes are red eyes just waiting to happen.


How long does weed eyes last?

Generally speaking, red eyes when high last 2-3 hours when smoking or vaping and 4-6 hours when consuming edibles.

Thankfully, marijuana eyes don’t last the whole time that THC lasts in your body- which is detectable for anywhere from 1 to 13 days according to one study.

However, there are stories of heavy users taking a month or more until their tests come up negative.

Point being, we’d all be in trouble if red eyes from weed lasted that long! Even though a couple of hours is a little inconvenient, it sure beats if we were stuck with stoned eyes for the whole time THC remained in our systems.

How to prevent red eyes from weed

If you want to prevent red eyes from weed, opt for low-THC strains. Verts Neighborhood Dispensaries definitely carry what you need to keep your eyes as white as ever, so check us out!

But if you’re set on it, drinking enough water is the best way to proactively prevent red eyes from weed if you’re going to be consuming a lot of THC (which we can also help with!). 

Chugging water before a big session can make all the difference between firetruck-red eyes and beautifully clear whites. 

Another way to prevent red eyes from weed is to lay off the caffeine. Caffeine also increases blood flow, which won’t help your case. And as a double whammy, it’s a diuretic, aka it’ll dehydrate you like it’s nobody’s business.

Which brings us full circle back to hydration. So drink up!

How to get rid of weed eyes

Wondering if someone is a stoner? Ask them for eye drops and you’ll quickly have your answer.

Eye drops are the perfect solution to weed eyes when high. Portable, discreet, and effective. The lifeblood of stoner college students for decades.

Cold temperature can also help get rid of red eyes from smoking. Cold temps applied via cold compress or ice pack will lead to vasoconstriction, which will effectively un-dilate your blood vessels and capillaries. 

But do not put ice or an icepack directly on your eyelids! Be sure to put a towel between your eyes and the ice since eyes are so delicate and prone to damage. Cold compresses made with a towel and cold water can be placed directly on the eyelids unless it ends up being too cold for comfort, in which case you should let it warm up a bit before reapplying.

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