As marijuana use for medical and recreational use has become more common, there has been renewed interest in the potential benefits of the cannabis plant. The changes in the legal status of cannabis have enabled the scientific research of the plant to continue, confirming many earlier findings, while also discovering new cannabis-derived treatments. Some of the initial medical research projects involving marijuana sought to find out if the plant could be an effective treatment for glaucoma.
What is Glaucoma?
Glaucoma is a medical condition that can cause permanent loss of vision. The disease is associated with a buildup of abnormally high pressure in the eye called intraocular pressure. The increased pressure in the eye can degrade the optic nerve, causing vision to worsen over time. Left untreated, glaucoma may cause irreversible vision loss and even total blindness within a few years.
Glaucoma tends to be hereditary, with symptoms usually appearing later in life. Many types of glaucoma have no symptoms or warning signs, and the loss of vision is gradual. The lack of early symptoms often causes the condition to go undetected until the loss of vision is at a later stage.
It is estimated that glaucoma affects over 3 million people in the United States alone, with almost half of them unaware that they have the condition. While glaucoma has no early indications or pain, for people over the age of 60, it is one of the leading causes of blindness.
There is currently no known cure for glaucoma, and an eye exam is the only way to diagnose the condition, so regular visits to the eye doctor are critical. If your optic nerve is severely damaged and you lose vision, it is permanent. Still, regular eye exams can detect the disease early, enabling an effective treatment plan to be developed. When diagnosed early, treatments that lower the ocular pressure allow most patients to keep their vision.
Cannabis Can Help with Glaucoma
The primary goal in the treatment of glaucoma is to lower the ocular pressure. Depending on the severity of the condition, glaucoma is typically treated with eye drops or surgical procedures. Most glaucoma patients receive prescription eye drops that reduce the pressure in the eye to a level where the optic nerve is not further damaged. Unfortunately, like many prescription medications, some patients do not tolerate daily eye drops very well, and require additional or alternative glaucoma therapies.
Studies have shown that ingesting cannabis can lower ocular pressure for glaucoma patients as well as people in general. A 1971 study, “Marijuana Smoking and Intraocular Pressure,” first examined the effects of cannabis on eye pressure. Participants in the study received eye examinations before and one hour after smoking cannabis. Researchers found that after smoking marijuana, the participant’s ocular pressure was decreased by 30 percent. Further research has confirmed these effects and also discovered that not only smoking marijuana but taking the cannabinoid THC orally also reduces ocular pressure.
Current research has found that glaucoma has numerous similarities with neurodegenerative diseases such as Alzheimer’s and Parkinson’s disease. This research suggests that in addition to elevated eye pressure, other factors may also contribute to the progression of the condition. Cannabis is known for its neuroprotectant properties and, while more research is needed, shows promise as an inhibitor for glaucoma.