Home > Online Clinic News > Viagra and Blindness Claims

Latest News

by Robert MacKay, Sunday, March 17, 2013 | Categories: Viagra

The importance of being informed about potential side effects of any medication cannot be understated. However, when new medications come out there is always a possibility that reports of side effects unknown to the pharmaceutical companies and researchers emerge in the post marketing environment. But sometimes there are reports of potential side effects that only affect a few people and these should not necessarily be construed as a having widespread applicability. A few incidents of blindness following Viagra use have been reported in the United States but what is the validity of the claim?

It is commonly known that transient visual disturbances can occur as a result of taking Viagra. However, these side effects are noted on the rarer end of the scale and appear to occur in 4% of the study participants. It has been argued that this is due to that fact that sildenafil, the active ingredient in Viagra, partially blocks an enzyme called PDE6, which is known to mediate the process of transduction. Reviews and meta-analyses of clinical studies suggest that these side effects can be lessened with appropriate dosage adjustment and animal studies indicate that sildenafil does not have any major effect upon a normal retina. Moreover, long-term toxicology studies to date do not demonstrate any adverse visual side effects upon normal retinae. There is little possibility that such a large number of studies that have systematically investigated the drug would have such low quality or be unreliable.

Having said that, we understand that there have been 50 lawsuits against Pfizer (the manufacturer of Viagra) where individuals have claimed to have lost their sight as a result of using Viagra. However, on examination most of these men had type 2 diabetes, which is widely known to cause blindness. We need to also consider these 50 cases within the context of over 23 million men having been prescribed Viagra globally without similar side effects.

There are certain medical conditions related to vision which definitely contraindicate patients for Viagra. For example, we would never prescribe for any patient who had retinitis pigmentosa or macular degeneration. However, we are confident that sildenafil does not cause blindness. The men in the US who have experienced blindness probably have their type 2 diabetes to blame and that in turn can be blamed on their bad lifestyle choices over the years. It is important not to have a closed mind, but Viagra really is one of the safest medications around.

More information can be read about Viagra and visual disturbances here.





 
We use cookies on this website. By using this site, you agree that we may store and access cookies on your device. Find out more Close