"...it’s well known that smoking marijuana can reduce pressure within the eye, a hallmark of the disease.
But the drug may also reduce the blood supply to the optic nerve - the last thing a glaucoma sufferer needs - and it doesn’t seem to prevent blindness. Even if marijuana could save eyes, smoking it enough would take extraordinary effort. ‘In order to substantially reduce eye pressure,’ says Dr. Harry Quigley of John Hopkins University’s Wilmer Eye Institute, ‘you’d have to be stoned all the time.’"
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Can Marijuana be Medicine?, Newsweek, February 3, 1997
"Glaucoma? It borders on malpractice to give marijuana for glaucoma. While it can reduce intraocular pressure (with huge doses of pot), it also can constrict blood supply to the optic nerve, exacerbating vision problems. There are far safer and better drugs."
-- Pot as Medicine, Washington Post, February 7, 1997)