During clinical studies, there were a number of other side effects that occurred in less than 2 percent of people taking
Viagra. It is difficult to tell whether these side effects are caused by Viagra or something else.
Some of these possible Viagra side effects include, but are not limited to:
In rare cases, there have also been serious problems that occur in the heart, brain, or blood vessels. These include:
In these cases, most of the people had cardiovascular (heart or blood vessel) risk factors. Also, these side effects occurred during or shortly after sexual activity. Therefore, it is difficult to tell whether the problems were related to Viagra, the person's existing risk factors, sexual activity, or a combination of these.
There have also been rare cases of a condition called non-arteritic anterior ischemic optic neuropathy (NAION). This condition can lead to sudden loss of vision in one or both eyes
(see Viagra and Blindness for more information).
There have been reports of transient global amnesia possibly due to Viagra. Transient global amnesia is a temporary loss of short-term memory. People may not remember recent events and have an impaired ability to form new memories. It usually lasts 24 hours or less and typically has no long-term consequences.
