Medical marijuana patients across the country use cannabis to lower intraocular pressure (IOP), one of the main symptoms of glaucoma. Glaucoma is an eye disease of the optic nerve that affects more than 3 million Americans and is one of the most commonly cited reasons cannabis patients get medical marijuana. It’s an approved condition in all medical marijuana states, except for Vermont.
While the lack of major scientific studies concerning marijuana and glaucoma cause many experts to question the benefits of cannabis for people with glaucoma, here are a few quotes from prominent sources that promote its use:
Paul Palmberg, MD, PhD, a glaucoma expert and National Institute of Health (NIH) medical marijuana panelist, said at a Feb. 20, 1997 conference:
I don’t think there’s any doubt about its [marijuana] effectiveness, at least in some people with glaucoma.
The World Health Organization (WHO), in its 1997 report Cannabis: A Health Perspective and Research Agenda, stated:
While THC has long been known to reduce the increased intraocular pressure of glaucoma, it has not been fully studied therapeutically….Therapeutic uses of cannabinoids are being demonstrated by controlled studies in the treatment of glaucoma.
The Institute of Medicine’s Mar. 1999 report “Marijuana and Medicine: Assessing the Science Base” stated:
High intraocular pressure (IOP) is a known risk factor for glaucoma and can, indeed, be reduced by cannabinoids and marijuana.
GW Pharmaceuticals stated on its website (accessed Jan. 2004):
The ability of cannabis and THC to lower intra-ocular pressure in glaucoma was serendipitously discovered in the late 1970’s by a variety of patients and researchers. Several patients in the US Compassionate Use Investigational New Drug Program maintained their vision while employing large amounts of daily cannabis in situations where standard drug therapy failed….
An emerging concept is that glaucoma represents a progressive vascular retinopathy that requires a neuroprotectant to preserve vision. Some of the resulting optic nerve damage accrues due to NMDA hyperexcitability, an effect that THC and CBD may counter as neuroprotective antioxidants.
Thus, glaucoma is an area where cannabis and cannabinoids may offer particular advantages over available single ingredient ocular anti-hypertensive agents. Delivery methods remain an exacting challenge.
If you or someone you love is afflicted with glaucoma, medical marijuana may help. But you must first ensure you are in compliance with your state laws. In all medical marijuana states, the first step is to see a qualified medical marijuana doctor.