Sildenafil Citrate is a medication used to deal with impotence, given approval by the US Food and medication Administration (FDA) in March 1998. Sildenafil Citrate works by blocking the enzyme phosphodiesterase, which breaks down cGMP, a relaxant of smooth muscle. The cGMP can enable for higher dilation of blood vessels (dilated by nitric oxide) and it is the increase in blood flow that enables two thirds of men dealing with from E.D. to succesfully achieve an erection. It must be taken up to an hour before intercourse. Side effects include headaches and fainting (due to dilation of blood vessels), and blue-tinted sight. The inhibition of phophodiesterase in the eye might result in damage to the retina as a side effect of taking Sildenafil Citrate .

At the start of 2000, Sildenafil Citrate sales accounted for 92 percent of the worldwide market for prescription E.D. pills. By 2007, Sildenafil Citrate ’s worldwide share had plummeted to about 50 percent due to numerous factors, not excluding the entry of Cialis and Levitra, along with numerous other counterfeits and clones, and reports of sight loss in people taking PDE5 inhibitors.

Sildenafil is metabolised by liver enzymes and excreted by both the liver and kidneys. When consumed with a high-fat meal, absorption is lessened; the amount of time it takes to reach the maximum plasma concentration increases to up to one hour, and the maximum concentration itself is decreased by nearly one-third.

Recommendations are given to men with kidney or liver impairments, and men over age 65, start at the lowest possible dosage of Sildenafil Citrate (25 mg). Clinical studies have indicated that the medication builds up in the plasma of these patients to a concentration that is between three and eight times higher than normal. Caution is also recommended in prescribing the medication to individuals with retinitis pigtosa, a unusual genetic eye disorder. Sildenafil Citrate should only be taken once per day by anyone.

Sildenafil was initially created in 1991 as a medication for angina, or chest pain. The medication, marketed under the name Sildenafil Citrate , taken FDA market clearance as a treattfor impotence in March 1998, and since that time it has been given for over 10 million men worldwide. It was the first oral medication given approval for ED deal withment. A newer medication, tadalafil, has been created to deal with men who do not respond to sildenafil citrate. Tadalafil has had preliminary approval in the European Union (EU), and is in the final stages of regulatory approval in Canada as of November 2002.

Sildenafil Citrate does not increase sexual desire. Sexual stimulation and arousal are needed for the medication to be effective. Despite its widespread use as a recreational medication, it is not an aphrodisiac and there is no clinical evidence that it increases sexual performance in men who are not suffering from ED.