Cannabis Facts

Red eyes and marijuana consumption often go hand in hand. Lets dive right into the reasons why it occurs, probability factors and what to do about it:

Red Eyes and Marijuana – Why It Occurs

  1. The primary and most common reason is due to the THC in cannabis, whether smoked, vaporized or digested (remember combustion destroys more THC than other consumption methods). This psychoactive cannabinoid decreases blood pressure which dilates the blood vessels and increases blood flow throughout the body.  The arteries in the eye-ball expand from the decreased blood pressure. These enlarged arteries are what produce the bloodshot red eye effect. It is precisely this effect on the human eye that makes cannabis an effective medicine for glaucoma. Studies in the 1970s showed marijuana, when smoked or eaten, effectively lowers intraocular pressure by about 25%, as much as standard medications.
  2. Some people’s eyes are more easily irritated by smoke of any kind. If you’re smoking cannabis for an extended period in a poorly ventilated space and your eyes are easily irritated by smoke, you may get red eyes.
  3. A small percentage of the population has cannabis allergies. Cannabis produces pollen and that can produce an allergic reaction in some people. However, if you have an allergy to marijuana it will be a lot more than just red eyes, such as hives, swelling, or itchy skin, etc.


Red Eyes and Marijuana – Probability Factors

  • Genetics: Some folks are just more pre-disposed towards red eye from using cannabis. For example, even moderately chlorinated pool water turns my eyes red in record time but cannabis almost never impacts my eyes.
  • Tolerance: More regular users of cannabis tend to develop resistance to red eyes versus new and infrequent users.
  • Strain Type: Cannabis contains a plethora of compounds, from cannabinoids to terpenoids, interacting with each other in countless ways. Some strains produce more red eye than others.
  • Stay Hydrated: Some believe staying hydrated helps minimize the frequency and duration of ganja induced red eye bouts. I haven’t seen conclusive evidence but staying hydrated is never a bad thing anyway.


Red Eyes and Marijuana – What to Do About It

  • Chemical Eye Drops: Reach for something like Visine Advanced Redness Plus Irritation Relief Eye Drops.
  • Artificial Tears: Don’t overuse the Visine. Try to use artificial tears when possible like Clear Eyes Natural Tears Eye Drops.
  • Lay Low, Ride It Out: Grab some shades or hide from the sun an ride it out for the two to three hours it may last. A nap never hurts either.
  • Say “Fuck It”: I get a lot of shit done every day. Yes, I like to enjoy cannabis, I have red eyes and I don’t give a fuck if others have a problem with it.


And remember Principal Brian Lewis knows!


It's the dilation of the blood vessels that causes the drop in blood pressure... Not the other way around


They're not called arteries. They're blood vessels. Call them 'penguins' if you're not going to care or know the difference.


I have had chronic dry eyes and also work on the computer while I am eating cookings :). My eyes from a combination of things hurt and they get red. What I do use which is a natural tear product about 3 times a day.

Here is the product