Seeing Is Believing: Medical Cannabis and Glaucoma

Glaucoma is a disease that damages your eye’s optic nerve. It usually happens when fluid builds up in the front part of your eye. That extra fluid increases the pressure in your eye, damaging the optic nerve. Blindness from glaucoma can often be prevented with early treatment.

What Causes Glaucoma

It’s the result of high fluid pressure inside your eye. This happens when the liquid in the front part of the eye doesn’t circulate the way it should. Normally, the fluid, called aqueous humor, flows out of your eye through a mesh-like channel. If this channel gets blocked, the liquid builds up. That’s what causes glaucoma. The reason for the blockage is unknown, but doctors do know it can be inherited, meaning it’s passed from parents to children. Less common causes include a blunt or chemical injury to your eye, severe eye infection, blocked blood vessels inside the eye, and inflammatory conditions.

Medical Cannabis Treatment

The ability to reduce eye pressure and ease the effects of glaucoma was the first scientifically confirmed health benefit of medical marijuana in 1970’s. This effect was discovered quite by accident by researchers, who were studying the tell-tale marijuana “red eye” in hopes of somehow using the phenomenon to help the DEA to narc out stoners. They incidentally found that cannabis reduced eye pressure by about 25 percent.

According to the American Glaucoma Society, cannabis has demonstrated the ability to lower IOP in both normal individuals and in those with glaucoma, and therefore might be a natural glaucoma treatment. One cautionary fact about cannabis’ ability to lower IOP is that it only works for a short time, so patients would have to use cannabis about every three hours.

An exciting finding in the past decade is the discovery of receptors for the active components of cannabis in the tissues of the eye itself, suggesting that local administration has the possibility of being effective. Furthermore, there is evidence from research in the brain that there may be properties of the cannabinoid components of cannabis that protect nerve cells like those in the optic nerve.

The CB2 receptors are also under intense investigation for their possible immunomodulatory effects. Cannabis has been proven to be a useful and effective anti-inflammatory for a range of different conditions. As understanding of the role inflammation has to play in the progression of the disease increases, it may well prove to be the case that cannabis also provides relief to glaucoma patients due to its anti-inflammatory properties.

Conclusion

The ability of cannabis to improve the symptoms of glaucoma has been demonstrated in various studies. This raises the hope that cannabis could protect the optic nerve not only through IOP lowering but also through a neuroprotective mechanism.