What You Need to Know About Cannabis and Glaucoma

Glaucoma spreads darkness around the world as the second leading cause of blindness. Estimates put the total number of suspected cases at over 60 million worldwide, including more than 3 million in the U.S.

A Natural Option For Glaucoma Treatment

If you’ve been warned that you could be a candidate for glaucoma, you may want to consider cannabis as a natural alternative to the prescription drugs that your eye doctor will likely recommend. But before you decide, it’s worth knowing the facts.

Glaucoma is an eye condition in which the optic nerve, which connects the eye to the brain, becomes damaged by a buildup of internal pressure. That usually happens over time due to a condition known as primary open angle glaucoma, which is caused by the drainage channels in the eye gradually becoming clogged over time.

But it also can come on suddenly, a condition known as acute angle closure glaucoma. This is an uncommon type caused by the drainage in the eye becoming suddenly blocked, which can raise the pressure inside the eye very quickly.

It’s urgent that you see an ophthalmologist quickly if you experience symptoms of that condition, which can include severe headache; eye pain; nausea and vomiting; blurred vision; halos around lights and eye redness.

Bottom line: If you haven’t had a recent eye exam, you should probably get one and make sure that your ophthalmologist tests your intraocular pressure, or IOP, which is done using a procedure known as tonometry. It formerly was done using a puff of air directed at the eyeball, but now most ophthalmologists use a more accurate device that measures pressure by direct contact with the eye.

If the pressure inside your eye is found to be high – normal is generally considered between 10 and 21 “millimeters of mercury,” a scale used to record eye pressure — the eye doctor will likely recommend treating it with prescription medication. Or, if it’s considered a serious case where your vision is at stake, via surgery.

Common Drug Treatment Side Effects

Eyedrops to help increase the drainage of the eye and lower fluid pressure are the most common drug treatment. But they can have side effects, as noted by the Glaucoma Research Foundation. Among them are fatigue, drowsiness, headache, mental fuzziness, loss of strength, depression, kidney stones and frequent urination.

It should come as no surprise, though that ophthalmologists who receive money from pharmaceutical manufacturers are more likely to prescribe medications promoted by those companies than similar drugs that are less costly, according to a 2016 study by researchers at the Washington University School of Medicine in St. Louis published in the journal JAMA Ophthalmology. That has, after all, been shown to occur again and again in the symbiotic relationship between doctors and drug makers.

That’s worth considering when you read the American Academy of Ophthalmology’s position paper recommending against the use of cannabis as a natural alternative to prescription drugs.

The paper correctly notes that a 2006 study published in Journal of Glaucoma found that THC – an active ingredient in cannabis associated with the “high” produced by the plant – lowered intraocular pressure (IOP) within the eyeball. It also dutifully reported that the research was supported by the National Eye Institute, a division of the federal National Institutes of Health.

But the industry group’s recommendation against using cannabis largely focused on the fact that the effect was found to be relatively short-lived, typically lasting about three or four hours.

It said:

“This short period of time is a major drawback for the use of marijuana as a glaucoma treatment. Because glaucoma needs to be treated 24 hours a day, you would need to smoke marijuana six to eight times a day around the clock to receive the benefit of a consistently lowered IOP. Because of marijuana’s mood-altering effect, smoking so much of it daily would leave you too impaired to drive, operate equipment or function at the peak of your mental ability.”

Lower THC Doses Well Tolerated

This is all well and good until you take a closer look at the study, which noted that “a single 5 mg sublingual (under the tongue) dose of Δ-9-THC reduced the IOP temporarily and was well tolerated by most patients.”
To provide some context, most states considers 10mg to be a “single serving size” of cannabis. So, a dose of half that seems unlikely to incapacitate you.
Also, with edibles, you can use the delayed onset to your advantage, such as taking a slow-release product shortly before bedtime.

Bottom line is that if you are interested in exploring the benefits of cannabis in treating glaucoma you aren’t likely to get much support from your doctor.

The good news is that Greenlight Approved, a consumer education platform dedicated to “guiding the cannabis curious,” is there for you.

We believe when you start something new, it’s best to start slow. Gather all the information you can to make a safe informed decision. Let Greenlight Approved be your guide so your first experience with cannabis is an educated, safe and positive one. Let us direct you to premium product and brand options as well as participating retailers near you, at www.greenlightapproved.com.

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