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Older man with glaucoma talks with doctor on intake of PEA

PEA’s Promise as a Glaucoma Treatment

A clinical study shows the fatty acid PEA lowered eye pressure in glaucoma patients and improved retinal function. A human study found a 43% improvement in eye health.

Scientifically reviewed by: Dr. Crystal M. Gossard, DCN, CNS, LDN, in August 2023. Written by: Lisa Hawkins.

Glaucoma affects 80 million people around the world.

The cost incurred in the United States due to glaucoma is close to $3 billion yearly.1

It can’t be cured, and is one of the most common causes of blindness.2

Treatment is usually focused on topical eye drops that help to slow vision loss by reducing the excessive pressure in the eyeball that is an underlying feature of glaucoma.

A recent clinical trial adds to evidence that oral intake of palmitoylethanolamide (PEA) improves glaucoma scores alongside prescription eye drops.3

In the trial, PEA lowered damaging eye pressure in glaucoma patients and led to improvements on tests of retinal function.

Glaucoma and Vision Loss

Older man having right eye examined

About three million Americans suffer from glaucoma, a group of related eye diseases.1 They often have no symptoms until loss of vision begins.

In glaucoma, there is an increased pressure within the eye, referred to as intraocular pressure. This pressure results from a buildup of fluid in the eyeball.

As glaucoma worsens over time, it damages cells in the retina of the eye called the retinal ganglion cells in the optic nerve. These cells are responsible for passing visual information from the eye to the brain, where it’s formed into an image.

When these nerve cells and their fibers deteriorate, the result is gradual vision loss, eventually culminating in complete blindness if not successfully treated.

As these retinal cells die, input to the visual centers of the brain is lost.

Prescription eye drops can slow the progression of this vision loss. But nothing can reverse it yet in humans.

What is PEA?

Palmitoylethanolamide (PEA) is a fatty acid produced in the body in response to inflammation.

It is found in trace amounts in some food sources, including egg yolk and peanuts.

PEA has been used clinically for pain management and discomfort relief.

As they learn more about PEA, scientists have found that it has beneficial biological activity in other areas.4-6

How PEA Fights Glaucoma

PEA can help control glaucoma in different ways.

One of the main causes of glaucoma is the buildup of fluid, known as the aqueous humor, in the eye. This buildup leads to an increase in intraocular pressure.

PEA improves the outflow or drainage of the aqueous humor, reducing fluid levels.7-11 Human studies have shown that oral intake of 600 mg of PEA daily significantly lowers intraocular pressure.7,11

In one randomized, placebo-controlled study, 300 mg of PEA twice per day for three months resulted in reduced intraocular pressure and improved endothelial function (measured by flow-mediated dilation).12

In addition, animal studies show that PEA has neuroprotective effects, shielding nerve cells in the retina and the brain from damage due to various forms of injury.13-16

Clinical Improvements

Man with head back using eye drops

Researchers in Italy recently conducted a clinical trial of PEA in glaucoma patients.3

People who were already taking eye-drop medications for glaucoma were randomized into two groups. One continued the current therapy. The second group also took 600 mg of PEA daily.3

A non-invasive test called a pattern electroretinogram (PERG) was performed on all subjects. This measures eye health by testing the function of the retinal ganglion cells that are damaged by glaucoma.17,18

At the end of the study, patients who took PEA had PERG test scores that were approximately 43% improved compared to their starting values and the values of subjects who did not receive PEA.

The intraocular pressure of all subjects was also recorded. Those taking PEA had significantly lower eye intraocular pressure, (an average reduction of about 1.58 points).3

A prior trial of glaucoma patients established that for each 1 mmHg reduction in intraocular pressure, the risk of progression of loss is reduced by 10%.19 That means that this degree of improvement equates to a potential reduction in the risk of progression of glaucoma symptoms.3

Quality-of-life scores were also calculated using a vision-specific questionnaire designed by the National Eye Institute. Subjects taking PEA scored an average 6.89 points higher on the quality-of-life exam compared to those not taking PEA.3

These results show significant benefits for patients suffering from any stage of glaucoma.


Glaucoma is a chronic and progressive eye disease. It is one of the most common causes of blindness in adults.

PEA is a compound produced in small amounts in the body. Oral intake of PEA is often used to control pain.

Studies have demonstrated that PEA can help control glaucoma as well, protecting the eyes and vision in several different ways.

In 2020, a study was published that evaluated the use of PEA as an add-on glaucoma therapy to prescription eye drops. It found that a 600 mg dosage of PEA daily lowered damaging eye pressure and improved retinal cell function and quality of life.

PEA holds promise as a glaucoma adjuvant alongside conventional medications.

If you have any questions on the scientific content of this article, please call a Life Extension® Wellness Specialist at 1-866-864-3027.


  1. Available at: Accessed January 28, 2020.
  2. Available at: Accessed January 28, 2020.
  3. Rossi GCM, Scudeller L, Lumini C, et al. Effect of palmitoylethanolamide on inner retinal function in glaucoma: a randomized, single blind, crossover, clinical trial by pattern-electroretinogram. Sci Rep. 2020 Jun 26;10(1):10468.
  4. Lambert DM, Vandevoorde S, Jonsson KO, et al. The palmitoylethanolamide family: a new class of anti-inflammatory agents? Curr Med Chem. 2002 Mar;9(6):663-74.
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  13. Levkovitch-Verbin H. Retinal ganglion cell apoptotic pathway in glaucoma: Initiating and downstream mechanisms. Prog Brain Res. 2015;220:37-57.
  14. Nucci C, Gasperi V, Tartaglione R, et al. Involvement of the endocannabinoid system in retinal damage after high intraocular pressure-induced ischemia in rats. Invest Ophthalmol Vis Sci. 2007 Jul;48(7):2997-3004.
  15. Rapino C, Tortolani D, Scipioni L, et al. Neuroprotection by (endo)Cannabinoids in Glaucoma and Retinal Neurodegenerative Diseases. Curr Neuropharmacol. 2018;16(7):959-70.
  16. Yazulla S. Endocannabinoids in the retina: from marijuana to neuroprotection. Prog Retin Eye Res. 2008 Sep;27(5): 501-26.
  17. Falsini B, Marangoni D, Salgarello T, et al. Structure-function relationship in ocular hypertension and glaucoma: interindividual and interocular analysis by OCT and pattern ERG. Graefes Arch Clin Exp Ophthalmol. 2008 Aug;246(8):1153-62.
  18. Graham SL, Drance SM, Chauhan BC, et al. Comparison of psychophysical and electrophysiological testing in early glaucoma. Invest Ophthalmol Vis Sci. 1996 Dec;37(13):2651-62.
  19. Leske MC, Heijl A, Hussein M, et al. Factors for glaucoma progression and the effect of treatment: the early manifest glaucoma trial. Arch Ophthalmol. 2003 Jan;121(1):48-56.