WASHINGTON, Dec. 24 (UPI) -- The perception of marijuana's effects on glaucoma significantly outpace what research has shown, according to a new study that researchers said suggests the public needs to be re-educated on medical uses for the drug.
Marijuana has been legalized for medicinal or recreational purposes in 23 states and Washington, D.C., in recent years, based largely on voter referendums.
Many of the votes have been passed on a 1999 Institute of Medicine report on marijuana's possibly therapeutic effects for a range of medical conditions, including glaucoma. Researchers note that while marijuana can relieve the effects of glaucoma for three or four hours, patients would need to be dosed eight to ten times per day for a "sustained therapeutic effect."
Researchers in the new study, published in the Journal of the American Medical Association, said patients need to be educated on the drug and its specific effects on glaucoma -- which they note is not supported by scientific evidence.
"This study contributes to filling the gap in our knowledge about patients' perceptions toward using marijuana for glaucoma and their intentions to seek this therapeutic alternative," researchers wrote in the study. "Understanding these intentions will become even more important as states continue to legalize marijuana for recreational use (currently Washington, D.C., and 4 other states), as patients with glaucoma will then have access to marijuana without the need for a physician to prescribe this drug."
The researchers surveyed 204 patients who have glaucoma or were suspected to have it between February 1 and July 31, 2013, at a glaucoma clinic in Washington, D.C. The patients completed a survey on their glaucoma, knowledge about marijuana and its effects on the condition, satisfaction with their current treatment, and intentions to use marijuana for glaucoma.
The researchers said many patients had inaccurate expectations or knowledge about the drug's effects on glaucoma. False percentions of the efficacy of marijuana on glaucoma, satisfaction with current care and relevance of costs for marijuana versus their current treatment all factored in heavily on whether to use the drug for their condition.
Marijuana legalization, for medicinal or recreational purposes, has grown but researchers said there has been a disconnect between actual research-supported uses for the drug and popular expectation of what it can do.
"This strong public-driven shift toward legalization of medical marijuana seems to clash with the relatively weak scientific evidence supporting its therapeutic use, particularly for treatment of glaucoma," researchers wrote in a separate editorial, also published in the Journal of the American Medical Association. "Altering this complex web of beliefs, misconceptions, satisfaction, and discontent requires an equally intricate patient-centered approach if physicians who treat patients with glaucoma are to effectively influence patient perception and transcend the clash between scientific evidence and popular culture."