Medical marijuana can lower intraocular pressure (IOP), preventing damage to the optic nerve. Many glaucoma patients use medical cannabis because they cannot tolerate the side effects of glaucoma medications.

Eye pressure is measured in millimeters of mercury (mm Hg). Normal eye pressure ranges from 12-22 mm Hg. When IOP is higher than normal, but the patient does not show signs of glaucoma, the condition is referred to as ocular hypertension. High eye pressure alone does not cause glaucoma.

However, it is a significant risk factor. Individuals diagnosed with high eye pressure should have regular, comprehensive eye examinations by an eye-care professional to monitor signs of glaucoma.


Glaucoma is a group of diseases that damage the optic nerve, a cable that carries visual information from the eye to the brain.

In open-angle glaucoma, the most common form of the disease, fluid passing through the anterior chamber drains too slowly, leading to increased eye pressure (IOP). This pressure can damage the optic nerve, leading to vision lossor blindness. High blood pressure is also a risk factor.


Primary open-angle glaucoma – Blockage is caused by material shed by the inner eye, inflammation, or scarring from an injury or infection.

Angle-closure glaucoma – In some people, the iris is very close to the drainage angle and eventually grows over it.

Glaucoma is the second leading cause of blindness in the world.

Glaucoma is often hereditary and does not appear until after the age of 60, but it can be present in young people and even in newborn babies.

Vision loss from glaucoma cannot be restored. Early detection and treatment can prevent vision loss. Glaucoma is treated with medication to lower pressure in the eye, and in some cases, with surgery. Once diagnosed with glaucoma, you will need treatment for the rest of your life.


Most people with open-angle glaucoma do not notice any symptoms until they begin to develop blind spots in their side vision.

People with angle-closure glaucoma sometimes experience a sudden, acute attack, with severe pain in the eye or forehead, redness in the eye, headache, blurred vision, and nausea. This is a medical emergency requiring immediate attention.

Regular eye exams are important to detect glaucoma in its early stages.


Glaucoma is one of the most common conditions treated with medical marijuana. Some people cannot tolerate the side effects of medications prescribed for glaucoma, which include palpitations, tachycardia, and altered mental status.

During the 1970s, it was discovered that marijuana lowers IOP. However, the effect wore off after three or four hours. Today’s medical marijuana products have longer-lasting effects.

The structures of the eye have cannabinoid receptors CB1 and CB2, which respond to THC and other cannabinoids in medical marijuana.

Researchers believe that the compounds in medical cannabis stimulate microcirculation and reduce inflammation in the eye. Medical marijuana also lowers blood pressure and improves circulation.