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Why Does Weed Make Your Eyes Red?

By Last updated on June 8, 2022Last updated on June 8, 2022No Comments

The first thing people think of if you have red eyes is that you must be stoned.

When people get very high from smoking weed their eyes tend to get red and dry. This is a problem if you do not want people to know that you are intoxicated.

Lower blood pressure and dilated capillaries

Lower blood pressure and dilated capillaries

Following the consumption of weed products, you may experience an increase in blood pressure and heart rate. This is a result of the cannabinoids; the compounds that offer medicinal benefits of weed. An elevated heart rate and blood pressure level are perfectly normal and are very similar to certain physical activities such as sex or exercise.

5-10 minutes is all it usually takes for heart rates to go back to normal and for blood pressure to begin to decrease. Capillaries and blood vessels dilate when your blood pressure decreases. As your ocular capillaries dilate more blood travels to the eyes, thusly resulting in red eyes. This phenomenon also contributes to a reduction of intraocular pressure.

“It’s cannabis’ ability to reduce intraocular pressure in the eyes that makes it a potentially viable treatment for glaucoma, a group of eye disorders that causes damage to the optic nerves which can eventually lead to blindness. It also happens to explain why your eyes become bloodshot after smoking cannabis,” says Dr. Melanie Bone, who is a board-certified OB-GYN.

How do different cannabinoids affect eye redness?

THC is the cannabinoid most responsible for the increase in heart rate, blood pressure, and the opening of ocular capillaries, resulting in eye redness.

These symptoms become less apparent for those with higher THC tolerance levels.

CBD, on the other hand, along with CBN, or CBG, has an opposite effect on the eye. Blood pressure decreases when these non-psychoactive cannabinoids are consumed. Using a strain that is a CBD to THC ratio of 1:1 will help reduce eye redness for those who still want to experience some THC without giving themselves away.

How else does weed affect the eyes?

Pupils can dilate for many different reasons such as a change in light, sexual arousal, during complex cognitive jobs, and of course from certain drugs.

Mydriasis is the other name for pupil dilation and it occurs as one of two groups of muscle is engaged; the iris dilator and the iris sphincter. The parasympathetic nervous system (controls our body when we sleep) triggers the sphincter response and the sympathetic nervous symptom (regulates physiological responses including fight-or-flight) triggers the dilator.

Certain recreational drugs such as cocaine, ecstasy (MDMA), antidepressants, and amphetamines may spike serotonin levels in the brain. This regulates your emotional state. Serotonin agonizes the 5-HT2A receptors in the brain and also triggers the mydriasis reaction.

Drugs that evoke the release of dopamine will also evoke mydriasis. Cannabis is an example of these drugs. Pupils dilate due to dopamine when the adrenergic receptors are engaged, and as a result, increases adrenaline.

Steps to get rid of eye redness

Red eyes from THC consumption are completely safe and nothing to worry about. As mentioned earlier, it can actually lead to a cure for glaucoma. However, if you are looking to avoid red eyes in order to stay discreet about being high then there are some steps you can take.

  • High CBD, low THC strains: CBD does not increase blood flow the way that THC does, making it a convenient way to enjoy cannabinoids without getting red eyes.
  • Use eye drops: Certain brands are designed to decrease eye redness and are very effective at doing so.
  • Good hydration: If you are thoroughly hydrated then you will not succumb to eye dryness which can contribute to red eyes.
  • Patience is key: If all else fails then at least take the comfort of knowing that after an hour or so your eyes should return back to normal.
  • Hide red eyes behind sunglasses: It can be suspicious if you wear sunglasses indoors but it is also a fail-proof way to keep people from peeping your red eyes.
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