Inherited from birth, retinitis pigmentosa is a condition that currently affects an estimated 100,000 people in the US. It causes photoreceptors in the retina to die over time, resulting in severe vision and blindness if left untreated. No cure exists for the disease, but vitamin A regiments have proven beneficial, postponing blindness by up to 10 years in some patients
In fact, a group of researchers from Spain’s University of Alicante published a study earlier this month in the journal Experimental Eye Research that supports this claim. It suggests that cannabinoids may help slow vision loss in the case of retinitis pigmentosa.
Researchers Investigate Cannabinoids, Visual Deterioration
The treatment group, which received 100 mg/kg of the synthetic cannabinoid each day, performed significantly better on visual tasks when compared to the group that did not receive treatment.
“Rats treated with the THC-like structure also had 40% more photoreceptors, which play a major role in passing information about visual stimuli to the brain.”
With that said, the University of Alicante research team investigated what effects were to be had from cannabinoid treatments. Using rats as models, they were able to inhibit vision loss with a synthetic form of tetrahydrocannabinol (THC).
Brief history and target symptomatology: This 37 y/o PhD university research associate was diagnosed with retinitis pigmentosa (RP) at age 14. He experiences progressive vision loss, headaches, depression and insomnia.
Abstract: A 37-year old man with retinitis pigmentosa found relief of associated symptoms with cannabis and subjective slowdown in progression of vision loss.
Clinical response to Cannabis: Stress reduced;mood, headaches and insomnia have all improved with cannabis use.
Previous and current conventional therapies: Supplementation with antioxidant vitamins was ineffective. Serial electroretinopathies (ERG) were discontinued in his belief that the flashes of light caused further damage to his retina and “ophthalmologists only want photographs for their own collection.” His eyeglass prescription is reviewed annually to compensate for his increasing tunnel vision. He has not found significant improvement in his mood with psychotherapy.
Comments: RP is a genetic disease found in 1 in 4,000 people in the US. In patient’s case, it was traced to mutations in both parents’ X chromosome. There is no known cure; valproic acid, gene therapy and retinal transplantation are currently in the research stage. Administration of a THC analog to rats with chemically induced RP has shown reduction in the rate of degeneration of retinal photoreceptors. .