Sildenafil is the generic name, that is to say the active ingredient of a medication that is prescribed for erectile dysfunction (impotence, the inability to get or to maintain an erection for long enough to gain satisfaction from sexual activity). The most famous brand of sildenafil is Viagra (that is why Viagra has a capital ‘V’ but sildenafil does not have a capital ‘s’), the ‘little blue pill’ that revolutionised the treatment of erectile dysfunction.
Sildenafil was introduced on to the market in 1998, as a treatment for erectile dysfunction. Interestingly, however, sildenafil was not developed for treating this condition, it was being developed as a treatment for angina when its useful ‘side effect’ was discovered. It is estimated that over half of all men between the ages of forty and seventy have problems getting or maintaining an erection at some point, so to say that the advent of sildenafil revolutionised some men’s lives would almost be an understatement.
Sildenafil works by increasing the flow of blood to the penis so a man can gain an erection.
Sildenafil is what is known as a phosphodiesterase type 5 inhibitor. These types of medicines work by inhibiting a chemical in the human body that is called phosphodiesterase type 5.
All medicines may, potentially, cause side effects. Anything that causes a change in the way the body functions may result in a side effect.
A very common side effect (affects more than one in ten people) of sildenafil is headache. Common side effects (affects between one in ten and one in a hundred people) include dizziness, flushing, nasal congestion and indigestion.