How Does It Work?When a man is sexually aroused, the body releases certain chemicals that relax the muscles in the penis. Normally, these muscles are constricted so that blood cannot flow into the penis. When the muscles relax, large amounts of blood are able to enter the penis. It is this blood flow into the penis that causes it to become erect.
An enzyme called phosphodiesterase type-5 (PDE5) is involved in breaking down the chemicals that caused the penis muscles to relax in the first place. When these chemicals are broken down, the muscles constrict, blood leaves the penis, and the erection goes away.
Like other PDE5 inhibitors, avanafil works by blocking PDE5. As a result, the chemicals that cause the penis muscles to relax remain active and blood can flow into the penis, resulting in an erection.
Clinical Effects of AvanafilAvanafil has been studied in clinical trials involving men with erectile dysfunction. In these studies, more men who took avanafil were able to get and keep an erection than men given a placebo (a "sugar pill" that does not contain any active ingredients). Specifically, in one study, up to 57.1 percent of men who took avanafil were able to maintain an erection long enough to have successful intercourse, compared with 27 percent of the men who took the placebo.
In another study, avanafil was evaluated in men with diabetes who had erectile dysfunction. In this study, up to 40 percent of the men taking avanafil were able to keep an erection long enough to have successful intercourse, compared with 20.5 percent of the men taking a placebo.
When and How to Take This MedicationSome general considerations to keep in mind during treatment with avanafil include the following:
- Avanafil comes in the form of a tablet. It is normally taken by mouth about 30 minutes prior to sexual activity.
- Do not use more than one tablet in a 24-hour period.
- This medication can be taken with or without food. Try taking it with food if it seems to bother your stomach.
- Avanafil will not cause an erection without sexual stimulation.
- For the medication to work properly, it must be taken as prescribed.