What is Glaucoma and how does it impact patients?
Glaucoma is a debilitating disease of the eyes that can affect vision and lead to blindness. It can damage the optic nerve behind the because of high eye pressure— what’s known as “intraocular pressure”, or ocular hypertension by doctors1. The optic nerve connects the eye to the brain, and many factors can play a part in damaging it, not just eye pressure.
Over time, damage to the optic nerve can lead to diminished side vision, which can lead to blindness in some patients. The higher pressure behind the eye is a leading factor, and because marijuana has been known to lower blood pressure along with intraocular pressure, it has been proven to provide some temporary relief2.
Glaucoma & Treatment with Medicinal Cannabis
Medical marijuana has been encouraged as a treatment option for many different types of diseases, and its use for the treatment of glaucoma goes back as far and the 1970’s3.
The smoking of marijuana as a treatment helped lower intraocular pressure in people with glaucoma conditions in studies, and because of the research performed, there was additional investigation into whether one of the active ingredients in marijuana—tetrahydrocannabinol (THC), was effective in keeping the intraocular pressure low. These studies were backed by the National Eye Institute, which is a division of the National Institutes of Health, a federal agency4.
In the last 10 years, there has been a breakthrough in research efforts that have found that eye tissue itself contains some active components found in marijuana that may help offer some protection to nerve cells that share characteristics to those found in the optic nerve5.
This would suggest that the possibility of dispensing the effective components of medicinal cannabis to eye tissue through eye drops, or by mouth and under the tongue, has a long-range possibility of being effective in treating glaucoma. Additionally, if certain drugs currently approved and used to treat glaucoma also contain cannabinoids, the possibility could exist that these drugs could incorporate the components active in marijuana and be developed pharmaceutically6.
Looking Ahead: Glaucoma and Medicinal Cannabis
Since the early days of research in the use of medical marijuana to assist in the treatment of diseases such as glaucoma, there have been a significant number of studies that have shown the effectiveness of certain cannabinoids such as cannabidiol, cannabigerol, endogenous cannabinoids, and a few synthetic cannabinoids can help lessen intraocular pressure when delivered to the body systemically or topically7.
Applying cannabinoids via an eye drop solution is considered the most ideal form of delivery to combat glaucoma. However, this method must take into consideration that this part of the eye has a low moisture solubility8.
Cannabinoids have the potential of turning into an effective treatment for glaucoma in that they help lessen some of the visual impairment due to eye pressure. There are properties that are neuroprotective and help minimize immediate damage to the optic nerves and do not cause adverse side effects9.
The exploration of other uses for medicinal cannabis to help treat other diseases of the eye can’t be ruled out. There are other powerful antioxidant components in cannabinoids that may be of benefit in treating conditions such age-related macular degeneration (AMD). And anti-inflammatory agents found in cannabinoid 2 receptors may become significantly useful in reducing inflammation for many other maladies10.