• Recent studies have shown cannabinoids to have potential preventative effects of blindness in Retinitis Pigmentosa sufferers
  • Anecdotal evidence also exists of blind patients temporarily regaining their sight after using medicinal marijuana
  • Could cannabis really offer hope to the blind?

Retinitis Pigmetosa (RP) is a rare, genetic disorder which involves a degeneration of cells in the retina affecting roughly 1 in 4,000 people worldwide. RP causes photoreceptors in the retina to die over time, resulting in severe vision and blindness if left untreated.

Unfortunately, there is no known cure for RP. Recent studies on medical cannabis, however, may offer some hope to those suffering from vision-related diseases, including Retinitis Pigmentosa and glaucoma.

Researchers at the University of Alicante in Spain conducted a study in 2014 to see the impact cannabinoids had on the vision of blind rats.

Using two groups of rats; those given a synthetic cannabinoid [the active chemicals found in cannabis] over a 90-day period, and those without, researchers found that those rats given the cannabinoids had 40% more photoreceptors in their eyes.

The study noted that the data suggested that cannabinoids are “potentially useful to delay the retinal degeneration in Retinitis Pigmentosa patients.”

Scientists researching cannabis plant

Researchers stressed that more research is needed before conclusions can be made from the data as they were unable to identify how cannabinoids are able to delay loss of vision in RP patients. But progress has been made on a stubborn disease which, so far, has been incurable by modern medicine.

“…cannabinoids are potentially useful to delay the retinal degeneration in Retinitis Pigmentosa patients.”

Other studies have found cannabinoids, such as CBD and THC, have potential neuroprotective effects which could prevent loss of vision and encourage overall eye health.

The most recent research, conducted by researchers at Montreal Neurological Institute in Canada last year, found cannabinoids can improve low-light vision by making cells in the retina more sensitive to light. These results suggest benefit cannabis could provide a significant benefit in the treatment of degenerative eye diseases.

Previous research from Jia Chen in 2005 found both CBD and THC function as neuroprotective agents and antioxidants, allowing them to increase the chance of cell survival within the eyes.

Our body’s endocannabinoid system plays a vital role in the regulation of vasoactivity in our eyes, as indicated by research from Spanish researchers in 2010, who found that THC and CBD decrease intraocular pressure, providing the groundwork for a potential treatment of glaucoma.

While there is no definitive answer, yet, on whether or not cannabinoids can be truly effective in treating and even preventing blindness caused by degenerative retinas, there is certainly promise.

References and further Reading

http://www.sciencedirect.com/science/article/pii/S0014483514000347

https://elifesciences.org/articles/15932

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1824211/

http://www.elsevier.es/ficheros/publicaciones/03656691/addon/S036566911000290X/S300/en/296v86n01a90001302pdf001_2.pdf