cannabis glaucoma, miss envy

A Guide to Cannabis and CBD For Glaucoma

Learn the research and use of cannabis and CBD for Glaucoma patients.

What is Glaucoma? 

Glaucoma is a disease of the optic nerve. The optic nerve receives light-generated nerve impulses from the retina and transmits these to the brain, where we recognize those electrical signals as vision.

Glaucoma is characterized by a pattern of progressive damage to the optic nerve that generally begins with a subtle loss of side vision (peripheral vision). If untreated it can lead to blindness.

For more information related to the symptoms and causes of glaucoma click here

Glaucoma and Cannabis

One of the major causes of optic nerve damage associated with glaucoma is higher-than-normal pressure within the eye (intraocular pressure or “IOP”). Currently, the only way to control glaucoma, and prevent vision loss, is to lower IOP levels.

Marijuana and THC have been shown to lower IOP in 60% to 65% of both normal individuals and patients with glaucoma. The average IOP reduction in one study was about 25%. This effect has been reported when THC is inhaled or administered orally, sublingually, or intravenously. 

The problem with smoking cannabis to reduced IOP levels is that the duration of the effect is short, about 3 to 4 hours. Increasing the dose does appear to have a greater impact on IOP levels but the increased dose does not improve the length of the effects.

This is a problem because to maintain lowered IOP levels a person would have to be smoking six to eight times a day. Some doctors believe this could have a negative effect on the patient’s ability to function. Another issue identified is that smoking cannabis also lowers an individual’s blood pressure and this could lead to more damage to the optic nerve.

Though smoking may not be the best treatment method for glaucoma there are many alternatives to smoking cannabis. Some of which include vaping, tinctures, edibles etc. Another option is the use of CBD which does not create the psychoactive high that has some doctors concerned. 

CBD Oil and Glaucoma – Natural “Cure”

This pressure build up associated with glaucoma is caused by an excess release of a damaging chemical known as glutamate. This compound leads to the death of neurons in the eye after the formation of peroxynitrite. Scientific research has presented that CBD can prevent the formation of peroxynitrite. As a result, CBD will provide protection for the neurons in the eye.

 Also, cannabinoid receptors are prominent in the tissues in the eye that are responsible for regulating intraocular pressure (IOP). Which indicates they will be an effective treatment for that area.

Therefore cannabinoid treatments could be developed that serve two roles:

  • lowering IOP
  • protecting retinal cells.

Evidence suggests several cannabinoids including CBD and CBG (cannabigerol), may be good candidates to develop as therapeutic treatments. Particularly because even when administered topically (directly to the eye), they are well tolerated. 

How Can We Improve CBD Treatment for Glaucoma?

 The issue with existing cannabis-based glaucoma treatment is bioavailability (bioavailability is the proportion of a drug, or other substance, that enters the circulation when introduced into the body. Therefore it is the amount of the drug that is actually able to have an effect). Although topical application via eyedrops works best, it still means that only 5% of an administered dose reaches the target. This is why some people have resorted to either vaping CBD (a potent means of administration for glaucoma) or taking it as an oil in an effort to ensure that more of the active compound is actually “put to use.” 

 The use of CBD for treatment of glaucoma has been common since the 1980s and appears to be effective; though more research still needs to be done. The most effective method of consumption needs to be explored. The use of CBD drops directly to the eye also appears to be promising but more research needs to be done on the best way for CBD to be absorbed this way.

Marinol vs Cannabis

What is Marinol?

Marinol is the brand name for a synthetic form of THC called dronabinol. In May 1985, the FDA approved Marinol as a prescription medication for the treatment of nausea and vomiting caused by chemotherapy. It can also stimulate appetite, which led to the FDA extending the approval to AIDS patients suffering from anorexia and weight loss.

 In some cases Marinol by covered by health insurance but there are many significant problems with it.

Problems with Marinol: Why Cannabis and CBD Treatment is better

One of the biggest issues is the long list of side effects, some of which include:

  • drowsiness
  • dizziness
  • nausea
  • vomiting
  • clumsiness
  • trouble thinking clearly.

To read the entire list click here.

Also, since Marinol is made to be similar to THC is likely to create the same ‘high’ effect as smoking cannabis. This is in itself is not a problem, but the other cannabinoids in cannabis appear to change the effect it has on the brain. These other cannabinoids prevent possible damage to the users mental health. Therefore the psychological experience of those consuming cannabis products is often better than those who use Marinol.

Consuming cannabis also allows for the consumer to choose the more appropriate and most effective method of consumption. In comparison Marinol can only be consumed orally and it may take an hour or more to be effective. This delay is not only problematic in treating symptoms but it also makes it significantly more challenging to find the most effective dosage. This could lead to taking too much which could has the potential to cause other adverse effects.

At Envy we do not recommend taking Marinol when consuming cannabis. But if you are considering taking Marinol, or it is the only option for you, read some of this important information. Also consult your doctor first as Marinol may have an effect on other preexisting conditions or interact with current medications. 

CBD Dosage

 It seems as though a common recommended dose of CBD for glaucoma treatment is around 20 mg. For complete information about appropriate dosage of CBD click here.  As always we recommend that you speak to your doctor before treating yourself with cannabis. We also recommend starting with a small dose and working your way up to find a dose that is appropriate and effective for you.


(Tomida I, Azuara-Blanco A, House H, et al. Effect of sublingual application of cannabinoids on intraocular pressure: a pilot study. J Glaucoma.2006;15(5):349-353.

(Green K. Marijuana smoking vs cannabinoids for glaucoma therapy. Arch Ophthalmol. 1998;116(11):1433-1437.)