DOES MARIJUANA CAUSE VISION IMPAIRMENT? DOES IT HELP TREAT GLAUCOMA PRESSURE?

Typical discussions of marijuana and vision usually concern pot’s ability to help people with glaucoma and related legal or political issues. Now, according to a report from UPI [link], frequent marijuana use may be linked (to a limited degree) to vision impairment.  

Preliminary results of research from France, published in the December 2016 issue of JAMA Ophthalmology, centers on the brain’s ability to receive incoming visual information. The study found that some frequent pot users experience a slight delay in the retina-to-brain nerve functioning. The researchers say the delay could indicate the presence of low vision.

The French study is based on research involving just 52 participants, 28 of whom were regular marijuana users. “Regular marijuana users” are folks who said they used marijuana at least seven times a week. The experts stressed that the findings are preliminary and further research is needed before conclusions should be made.

Scientists have known for some time that marijuana has an impact on nervous system communications. However, the current study did not necessarily prove that regular smokers do actually experience vision impairment. Most of the participants in the study did not complain of any vision issues before the study began.

Critics of the French study said it used an extremely small pool of patients, visual impairment symptoms of participants were not known prior to the study, and other lifestyle factors, such as diet and cigarette smoking, were not included in the research.

RESEARCH ABOUT MARIJUANA’S ABILITY TO LOWER GLAUCOMA PRESSURE IS MORE CONCLUSIVE

Legal recreational and medical use of marijuana has made it easier for people to “self medicate” their glaucoma treatment without consulting a doctor. This means marijuana participants are easier to find for research.

The notion that marijuana can be helpful in treating glaucoma dates to the 1970s. Studies conducted then showed that smoking marijuana lowered the internal eye pressure of people with glaucoma. Additional studies have concluded that the active ingredient in pot – THC – does make internal eye pressure lower. However, it only lowers internal eye pressure for a short period of time, typically three or four hours.

This short period of time is considered a drawback for the use of marijuana as a glaucoma treatment. Because glaucoma needs to be treated 24 hours a day, a person medicating with pot could become too impaired to drive or operate equipment.