Cannabis Effects on The Eyes: What Science Says

How cannabis use affects your eyes

Cannabis is known to have multiple health benefits. But, did you know that cannabis can have a positive impact on eye health?

Many cannabis users have seen or have had a personal experience with the famous “red eye effect.”

After a lengthy session smoking, the most noticeable sign is red eyes. 

Even though some may find the obvious effects of cannabis on their eyes to be problematic, there are many amazing ways that cannabis can improve your eyesight.

Amazingly, cannabis use can positively impact treating certain eye diseases and potentially prevent blindness from developing.

Cannabis is truly a healing plant.

There are many studies that suggest the massive healing potential cannabis use has on eye health.

Here are a few different ways cannabis use affects your eyes.

cannabis and eye health

How Exactly Does Cannabis Affect The Eyes?

According to research, cannabis can affect every organ of the body, even the eyes. In fact, it may play a pivotal role in overall eye health.

Although it may sound unbelievable, cannabis compounds work in the eyes because they tap into one of largest cellular communications networks in vertebrates. 

This network is known as the endocannabinoid system (ECS). The ECS interacts with cannabis compounds by engaging a particular type of cell receptor known as a cannabinoid receptor. 

Furthermore, the human eye expresses high levels of a particular cannabinoid receptor, the CB1. 

These receptors are also present in vision processing centers of the brain. 

Preclinical investigations also indicate that the ECS plays a crucial role in our vision.

The Research Behind Cannabis Affecting Retinal Health

A 2016 primate experiment that you can find in the publication Neonatal Plasticity shows that manipulating cannabinoid receptors can alter the flow of electroretinographic waves through the retina. 

An electroretinogram measures these waves and records the eye’s electrical response to light stimuli.

Research findings show that the eye’s response is actually moderated by cannabinoid receptors.

In addition, this early research suggests that cannabis can potentially be a treament for eye diseases.

Cannabis can have a variety of eye-straining effects. Some effects are very impressive, such as an improvement in night vision. Others are not so pleasant. Such as the bloodshot eye effect when smoking. However, while this may be unpleasant for some. it is actually a sign of relaxation.

Furthermore, it is not uncommon for people to experience these effects soon after consumption.

1.) The Red Eye Symptom

Red eyes are not the most popular side effect of cannabis. 

Although having red eyes can be a blatant sign that you’ve been smoking, it is also an indication of relaxation from using the herb. 

Moreover, cannabis lowers blood pressure. This causes blood vessels to dilate and capillaries to shrink, which is what we commonly refer to as red eyes. 

A wider capillary means blood flows to the eyes more easily, which lowers intraocular pressure. This is a form of relaxation for the body. 

Furthermore, patients with painful ocular conditions (e.g. glaucoma) find this extremely helpful.

cannabis effects on eyes

2.) Enhancing Night Vision

Lab research such as the study above shows that cannabinoid-receptors seem to be able to aid the eyes’ response to light.

Further research suggests that cannabis compounds like psychoactive THC can interact with these receptors. 

These receptors are thought to enhance the ability to see in low light conditions. 

Moreover, researchers have been speculating for the past three decades that cannabis could potentially improve night vision. 

M.E. West, a pharmacologist, became a popular name in the 1990s for popularizing this theory. 

Furthermore, West took note that a Jamaican fisherman friend of his who drank a cannabis elixir regularly, had an “uncanny ability to see in the dark.” 

Furthermore, a small research study from 2004 examines the effects of traditional cannabis and synthetic THC in three people. 

The exact cannabis used was known as the “Kif” mix. 

Kif is essentially a mixture between cannabis and tobacco. 

Additionally, the experiment demonstrates that each of the individual’s marijuana consumption had a direct improvement and correlation with night vision. 

weed effects on eyes

3.) Visual processing

Recent evidence supports the idea that the brain’s endocannabinoid system plays a significant role in visual development. 

A joint study between research teams from the University of Waterloo, University of Auckland, and Brown University discovered that babies with exposure to cannabis in utero, scored significantly higher in visual processing tests. 

However, this is not to encourage cannabis consumption while pregnant as it could lead to numerous other negative side effects. 

Also note that the study was done through cannabis edible consumption and not smoking. 

The visual processing scores of babies who had exposure to alcohol were lower than those who had exposure to cannabis. 

In addition, those who had exposure to cannabis had better global motion perception as well.

While we are not recommending to take cannabis whilst pregnant, this does give support to the hypothesis that cannabinoids help the ECS and eyes and brain process visual information.

4.) Allergic Reaction

After smoking cannabis, it is not entirely unusual for people to have an allergic reaction. 

An allergic reaction to smoke, residual molds, or cannabis can cause this reaction. 

Itching, redness, and inflammation are common signs of allergic reactions to cannabis. 

Furthermore, in 2015, a research study by the American College of Allergy, Asthma, and Immunology suggests that cannabis allergies can cause eye irritation and itchy nasal passages for people who have had exposure to smoke, pollen, and plant material. 

The Relationship Between Eye Disease and Cannabis Use

Cannabis can have a wide range of effects on the eyes. 

Although much is still unknown about cannabis and its effects on eye health, increasing evidence points to the possibility that cannabis could be useful in treating many eye diseases. 

These diseases include the following:

1.) Glaucoma

One reason cannabis is so helpful for glaucoma patients is because of the notorious red eye symptom. 

As many are aware, glaucoma damages the optic neuron and is one of the leading causes of blindness. 

Since the 1970s, scientists have been researching the effects of marijuana on glaucoma. 

Inhaling cannabis shows a significant reduction in intraocular pressure in a study with 16 medically approved volunteers. 

Furthermore, intraocular pressure is what contributes to the pain, degeneration, and the development of this disease. 

Patients report relief about 3 to 4 hours after the cannabis treatment. 

The greatest and longest-lasting results were observed in patients with high blood pressure as well as severe glaucoma. 

Additionally, these findings were further solidified in separate studies done back in 2000 and 1980.

2.) Diabetic Retinopathy

A preclinical study from 2006 shows that CBD, a cannabis compound which does not produce a psychotropic “high”, can help protect the eyes for diabetics. 

Diabetic retinopathy is a side effect from diabetes. 

It damages the retina’s blood vessels. The retina is part of the eye that can detect light. 

It is the light-sensitive part of the eye that suffers from diabetic retinopathy. 

This causes the nerve cells to stop working, which in turn affects eyesight. 

CBD, as a powerful antioxidant, can reverse degeneration by reducing toxicity in the retina. 

On the other hand, there is a study suggesting that chronic cannabis intake could actually damage the retina. 

However, a 2006 study shows that certain cannabis compounds may be able to help protect the retina. 

Furthermore, it seems to be dependent on the method of usage.

Cannabis affects retina

3.) Neurodegenerative blindness

In 2014, a study from Experimental Eye Research shows that cannabis medicines could slow down degenerative blindness. 

Particularly, the effects of cannabis compounds were able to stop the death of photoreceptors within patients suffering from retinitis pigmentosa. 

Rodents were used as test subjects in this research. 

The synthetic cannabinoid was administered to rats for 90 days. After 3 months, scientists examined the progression of blindness. 

Furthermore, cannabinoid-treated rats had a remarkable 40% higher number of photoreceptors in comparison to their untreated counterparts. 

This shows that cannabis therapies may slow down the progression of neurodegenerative blindness. 

Additionally, research shows that the herb contains neuroprotective antioxidants, which can help in many age-associated conditions. Which further proves all the potential health benefits cannabis provide in regards to retinal health.

Cannabis is an astounding plant. When it comes to research around its healing powers, the research barely scratches the surface. 

Cannabis has many medicinal qualities that have yet to be researched and thus implemented in healing regimens.

Tired of relying on a lacking medical system for your health? Learn how to grow your own cannabis and use your own flower in your healing process.

We offer online classes you can take from the comfort of your home or in-person classes for a more hands-on approach. Learn how to be an expert cannabis cultivator in no time!

How has cannabis affected your eye health? Let us know!

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