How THC Affects Your Visual Sensations

You take that first puff and immediately feel the effects. Maybe it’s an initial cough or wave of relaxation, but your body and mind will soon experience the results of THC hitting your bloodstream.

Learn how THC affects your visual sensations, perceived and real, and what science has to say about it.

How THC Affects Your Eyes

You experience a “high” from weed because of its interaction with your endocannabinoid system. Everyone’s got one, and it naturally sends and receives cannabinoids throughout our bodies to control appetite, manage pain, and so much more. Adding additional cannabis compounds to this system engages the cannabinoid receptor and has different effects on the body.

The human eye expresses high levels of the CB1 cannabinoid receptor, meaning it is very affected when you smoke. Continue reading to discover what some of these effects are.

Bloodshot Eyes

Ever wonder why you get bloodshot eyes after smoking, vaping, and consuming marijuana? The THC lowers blood pressure which leads to dilated blood vessels and increased blood flow throughout the body, especially your eyes. When the blood vessels in your eyes expand, they become red and appear bloodshot.

Scientists are looking into this effect for its potential benefit to glaucoma patients. Glaucoma is a disease of the optic nerve, and many researchers believe that the increased eye pressure patients suffer from could potentially be reduced with marijuana usage. While the decrease in eye pressure from marijuana only lasts for a short period of time, scientists believe that it still has the potential to further research around the benefits of marijuana.

Better Night Vision?

From tadpoles to humans, many studies have looked into the effects of marijuana on retinas.

In the 1990s, a pharmacologist, M. E. West of the University of the West Indies in Kingston, Jamaica, found that local fishermen were better able to see at night and navigate their boats around coral reefs after ingesting herbal cannabis. Researchers have also studied the night vision abilities in of smokers of the Rif mountains of northern Morocco.

A more recent study investigated the changes in tadpole retinas after exposure to cannabinoids. They found that “one class of cannabinoid receptor, known as CB1, fired at higher frequencies allowing the tadpoles swimming in a petri dish to see better and flee predators in low light conditions.”

Visual Processing

Additionally, many studies have established that marijuana affects several visual processing functions, including visual acuity, contrast sensitivity, focus, and 3D vision. Interestingly, 90% of cannabis users believe marijuana has either no (or minimal) effect on their visual abilities.

Researchers are still studying the impacts and effects of marijuana on the human eye. Have you experienced any of these effects on your eyes after smoking?