About Viagra Viagra, an oral therapy for erectile dysfunction, is the citrate salt of Sildenafil, a selective inhibitor of cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase type 5 (PDE5). When the sexual stimulation causes local release of Nitric Oxide, inhibition of PDE5 by Sildenafil causes increased level of cGMP in the corpus cavernosum resulting in smooth muscle relaxation and inflow of blood to the corpus cavernosum. Viagra is formulated as blue, film-coated rounded-diamond-shaped tablets and is one of the most commonly sold drug for treating male erectile dysfunction or impotence. It is also used for treating pulmonary arterial hypertension (PAH). The drug was developed by the pharmaceutical company Pfizer. Viagra is also informally known as Vitamin V or the Blue Pill. Ingredients of Viagra Viagra is contra-indicated in patients on nitrate therapy and with a known hypersensitivity to any ingredient of the tablet. In addition to the active ingredient Sildenafil Citrate, each tablet contains the following inactive ingredients: microcrystalline cellulose, anhydrous dibasic calcium phosphate, croscarmellose sodium, magnesium stearate, hypromellose, titanium dioxide, lactose, triacetin, and FD & C Blue #2 Aluminum Lake. Comes in the strength of Viagra pills are blue and diamond-shaped with the words Pfizer engraved on one side, and its dosage in milligrams engraved on the other side. The various doses of Sildenafil for erectile dysfunction are 25mg, 50mg and 100mg, taken not more than once per day between 30 minutes and 4 hours prior to sexual intercourse. It is usually recommended to start with a dosage of 50mg (or even 25mg) and then lower or raise the dosage as appropriate. Side Effects of Viagra Common side effects include: Sneezing Headache Flushing Dyspepsia Palpitations; and/or Photophobia Priapism Severe hypotension Myocardial infarction Ventricular arrhythmias Stroke; and/or Increased intraocular pressure Care should be exercised by patients who are also taking Protease inhibitors for the treatment of HIV. Patients using protease inhibitors must limit their use of Sildenafil to no more than one 25mg dose every 48 hours. Protease inhibitors inhibit the metabolism of Sildenafil, effectively multiplying the plasma levels and increasing the incidence and severity of side-effects. Some Viagra users have also complained of blue vision (Cyanopsia), including blurriness and loss of peripheral vision. There is also the potential risk of sudden hearing loss associated with the use of PDE5 inhibitors. When used with an alpha blocker, hypotension (low blood pressure) may occur, but this effect does not occur if they are taken at least four hours apart. Availability of Viagra Buying Viagra can be safe, convenient, and affordable and is available at both online or offline pharmacies near you. Prior to buying Viagra online, always get a written prescription. Buy from a site that gives a street address and a telephone number. Better still, buy from a verified Internet Pharmacy Practice a certified online pharmacy. Buying the generic version of the drug is ill-advised as it could be fake, illegal, or without proven safety or effectiveness record. Amongst Viagras rare but serious adverse effects are:

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