The human vision changes after taking a high dose of erectile dysfunction drug

The vision of a man was tinged with red after taking too much sildenafil citrate, an ingredient in some erectile dysfunction drugs, researchers report. In a case study, doctors at Mount Sinai, New York City, said the case illustrated the fact that excessive use of the drug could lead to long-term or even irreversible damage.

The findings were published in the fall issue of the journal Retinal Cases. The researchers described in detail the case of a 31-year-old man who arrived at an emergency care clinic complaining of a red-tinted vision in both eyes for two days. He reported that the vision changes started after taking sildenafil citrate, which he ordered on the Internet.

The patient reported taking much more than the recommended dose of 50 mg. The authors note that sildenafil citrate can cause visual disturbances at a normal dose, but that symptoms usually disappear within 24 hours.

"People adhere to the philosophy that if a little is good, much better, this study shows how much of a large dose of a commonly used drug can be dangerous," said Dr. Richard Rosen, director of the research on the retina in New York. Infirmary of the eyes and ears of Mount Sinai (NYEE), said in a statement.

Doctors used high-tech imaging that allowed them to see microscopic lesions of the cones of the retina cells responsible for the color of the vision. They have been diagnosed with persistent retinal toxicity in humans due to the high dose of drug that damages the outer retina.

Despite various attempts at treatment, the tinted vision of the man did not improve more than a year after his diagnosis.

"Our findings should help physicians become aware of potential cellular changes in patients who may over-use the drug to better inform patients about the risks of overuse."