The study "Viagra" on the damage due to color vision does not really concern the drug against ED

Rlatest titles regarding a case report published in the fall issue of Retinal cases and brief reports gave the false impression that a man developed a red-tinged vision after using Viagra. In the retrospective article, a team of doctors described the precarious situation of a 31-year-old man who took a large dose of sildenafil citrate, the active ingredient in Viagra, in order to treat his erectile dysfunction. Instead of the desired effect, the man has developed a vision tinged with red. This is alarming, but a closer look reveals a crucial detail: the man did not take Viagra itself.

The confusion seems to come from a press release that was issued Monday by Mount Sinai Hospital in New York and strongly suggested that Viagra was to blame. In the original version, which has since been modified to correct this error, hospital officials said: "Researchers have shown that color vision problems caused by retinal damage at the cellular level may be due to a high dose of sildenafil citrate, the popular anti-erectile dysfunction drug. sold under the brand name Viagra. The document is not available online, but reverse obtained from Mount Sinai Hospital in PDF format.

Following this statement, the media made headlines, claiming that Viagra could cause eye damage.

But careful examination of the paper shows no evidence that the patient actually took Viagra. He endangered himself with something much more risky: a counterfeit version of the drug sold on the Internet.

Liquid sildenafil citrate ≠ Viagra

What the patient actually took was a liquid version of sildenafil citrate, the active chemical ingredient in Viagra. In addition, the researchers did not conduct any other studies on patients using other Pfizer products.

"Pfizer is aware of media information mistakenly reporting that Viagra is the drug associated with a case report published by Mount Sinai Hospital," said Steve Danehy, Pfizer's director of media relations. reverse. "According to the hospital statement, the person would have actually purchased liquid sildenafil online, without indicating whether a prescription had been provided, and then ingested an unspecified dose. It is important to note that no regulatory body has approved liquid sildenafil citrate for treating erectile dysfunction. "

As of the date of publication, Mount Sinai has not responded to reverseRequest for comments. The research team includes doctors from Mount Sinai, Columbia University and the Faculty of Medicine at the University of New York.

What has really happened?

In fact, the case report indicates that the patient's visual symptoms started shortly after taking a dose of liquid sildenafil citrate that he had purchased over the Internet. Although the approved dosage of sildenafil citrate in pill form varies from 25 to 100 milligrams, the patient thinks he has consumed "a lot more" than 50 milligrams per milliliter in its liquid dose. After drinking the bottle directly, he "began to notice a red tint to his vision accompanied by multicolored photopsies and a sensation of contrast" shortly after ingesting the substance, write the authors. Two days later, his doctors diagnosed him with persistent retinal toxicity. A year later, his vision has not improved, despite various treatments.

A subsequent examination of his retina at the microscopic level revealed that he had undergone microscopic lesions of the cones of the retina, cells that are related to color vision.

"Really seeing this type of structural change was unexpected, but it did explain the patient's symptoms," said Dr. Richard Rosen, principal investigator and director of retinal services at the Mount Sinai New York Eye and Ear Infirmary Clinic. original statement of Monday. "Although we know that color vision disorders are a well-described side effect of this drug, we have never been able to visualize the structural effect of the drug on the retina until present. "

"Our findings should help physicians become aware of potential cellular changes in patients who may over-use the drug so that patients are better informed about the risks of excessive consumption."

The link of Viagra to vision

Some studies have shown that at higher doses, Viagra can have minor effects on vision, primarily giving a blue – and not red – hue to vision, making the lights brighter. According to an analysis conducted in 2002 by the University of Pennsylvania School of Medicine, the drug does not appear to induce any long-term visual changes in long-term studies in patients taking the correct dosage.

Sildenafil citrate, on the other hand, is a chemical that relaxes the muscles of the walls of the blood vessels and increases blood flow, thus helping to induce erections during sexual stimulation. Viagra markets sildenafil citrate as a tablet – and not a liquid – for the treatment of erectile dysfunction, hence its nickname "little blue pill".

Counterfeit drugs are the real problem

It is incredibly easy to obtain counterfeit medicines containing sildenafil citrate that are marketed as erectile dysfunction treatments. Between 2004 and 2008, about 35.8 million counterfeit tablets of sildenafil citrate were seized in Europe; the profit margin of these sildenafil citrate counterfeit drugs is about 2,000 times higher than that of cocaine. According to Pfizer, Viagra is its most counterfeit medicine. Not surprisingly, studies show that taking these drugs exposes consumers to unnecessary health risks.

"There are many factors contributing to the rapid growth of the illicit market, such as the low risk of persecution, the potentially high financial return, and ease of distribution through Internet pharmacies," Tulane University School of Medicine urologists wrote in a report. of 2017. Taking illicit drugs, they write, "could directly harm consumers, because many illicit products contain harmful contaminants and inaccurate amounts of active ingredient without appropriate warnings".

According to the World Health Organization, the existence of "rogue" online pharmacies seriously threatens the health of consumers. WHO states that in more than In 50% of the cases, the drugs bought on the Internet on illegal sites have been counterfeited.

At the moment, it is unclear how much Sildenafil Citrate this patient consumed and what exactly he took. But he did not take Viagra and he probably did not get the results he was looking for.