Several scientific studies conclude cannabis lowers eye pressure in glaucoma patients, suggesting patients should explore the potential benefits and drawbacks of using medical marijuana.
Glaucoma is one of 21 conditions currently approved for treatment with medical marijuana in Ohio. Research on its use started in 1971, with a groundbreaking study published in the Journal of the American Medical Association.
In that early investigation, the authors of the research determined a link between smoking cannabis and a reduction in intraocular pressure, believed to be the primary cause of glaucoma. After inhaling marijuana, study subjects showed roughly a 30% drop in eye pressure. Since that time, more research has been done to thoroughly understand marijuana’s effect on glaucoma, a serious eye disease that often leads to blindness.
What is Glaucoma?
More than 60 million people worldwide have been stricken with glaucoma, with 9% of those over the age of 80 at risk of developing the disorder. A slowly developing disease, glaucoma results from an excessive collection of fluid between the lens and the back of the cornea. When this fluid, also known as aqueous humor, fails to drain properly, it impairs the optic nerve — the main vehicle by which images are transmitted to the brain.
Primary open-angle glaucoma (POAG) is the most common form of the disease, and is characterized by a progressive winnowing of peripheral or central eyesight. As the disease advances, POAG patients report “tunnel” vision. Without treatment, glaucoma sufferers may lose their eyesight completely.
Medical Marijuana and Glaucoma
Recent studies and commentary suggest that while medical marijuana has been shown to alleviate intraocular pressure (IOP), the effects may be short-lived and come with side effects. A paper published last year in Investigative Ophthalmology & Visual Science tested how the two main chemical properties of cannabis — Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) — affected cannabinoid-related receptors in the brain, including CB1, CB2, and GPR18.
For that study, researchers applied THC and CBD topically to lab mice. After examining the mice, researchers concluded THC did lower IOP for about eight hours, but the positive effect was more pronounced in males than females. CBD, meanwhile, raised IOP in some of the mice and seemed to cancel out THC’s IOP-lowering benefits when both substances were applied together.
Is Medical Marijuana Right for You?
More scientific inquiries are being conducted to clarify how cannabis lowers IOP in glaucoma patients. For now, it appears medical marijuana may be one of several therapies patients can choose from to potentially lower IOP in the eyes.
Medical marijuana is currently approved by the state of Ohio as a treatment option for glaucoma. If you’d like to know more about the advantages of therapeutic cannabis for treating glaucoma, make an appointment today with a specialist at Lakeland Medical Clinic. Our physicians are certified to recommend medical marijuana to patients with qualifying disorders.