For men who suffer from male impotency, Viagra is miracle drug. For many, Viagra has given them their sex life back and that is why many feel that "Viagra is life".
Sildenafil citrate is the scientific name for the drug known commericially as as Viagra, Revatio and also known under a variety of other trade names. It's primary purpose is to treat erectile dysfunction which we know more commonly as male impotency. Pfizer is the pharmaceutical company that developed and marketed the male impotency drug Viagra. Viagra works by inhibiting cGMP specific phosphodiesterase type 5, which is an enzyme that controls blood flow in the penis. Since its availability in 1998, Viagra is the prime treatment for male impotency; Viagra primary competitors on the market are Cialis and Levitra.
Drugs like Viagra have side effects and Viagra is no exception. Just about every drug such as Viagra has side effects that arise because the drug is flowing throughout the body and may affect parts of the body unintentionally. Viagra has some side effects of which patients need to be aware of. One of the more unusual side effects of Viagra is on vision. Viagra has a spillover effect on on the chemistry that affects vision. Viagra blocks PDE5 and also PDE6. PDE6 is used in the cone cells in the retina, therefore Viagra has a distinct effect on color vision. Patiends who take Viagra do notice a change in the way they perceive green and blue colors. Sometimes they see the world with a bluish tinge for several hours. Airline pilots, for example, can't take Viagra within 12 hours of a flight.
PDE5 is an enzyme that accepts cGMP and breaks it down. Viagra blocks PDE5 and keep it from doing its job. The active chemical in Viagra that causes this is called sildenafil citrate. It fits right into the PDE5 enzyme and disables it. When a man takes a Viagra pill, the sildenafil citrate flows throughout his body, but Viagra really only affects the PDE5 enzyme in the penis. Viagra stays in the bloodstream for about four hours, and then it is washed out of the blood by the liver and kidneys.
In summary Viagra works in the following manner to treat erectile dysfunction: