Studies performed in the 1970s reported that smoking marijuana could lower eye pressure. Other studies have been inconclusive. Newer reviews by the National Eye Institute and the Institute of Medicine show that there is no scientific evidence that marijuana is more effective than the medications currently available.
As for legality, you may have heard about the political battles to legalize marijuana for medicinal purposes, including the treatment of glaucoma. A few states have passed laws legalizing marijuana for treatment purposes. However, it remains against federal law for doctors to prescribe marijuana.
Yes, it can and has been used successfully to treat glaucoma and is legal for anyone who has a medical necessity to use the least harmful alternative to prescription drugs that do not work nearly as well. Being a survivor of a large-mass fibrosarcoma tumor in my head (craniotomy performed May 2012) and subsequent radiation-therapy my right optic nerve was damaged and I was told to just expect to lose sight in that eye. I have been using smoked cannabis (as well as prescribed Cesamet/Nabilone) and, though the eye produces no tears, I can still see and have only minimal, controlled, pain/burning, etc. Please check the link for a more detailed explanation of the legality of medical use as the law stands currently.http://www.healthlawservices.org/2/post/2014/06/open-letter-to-law-enforcement.html
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