How was Viagra discovered?

By accident, in the sense that it was not being developed for erections. Sildenafil, the first selective PDE5 inhibitor, "has evolved from a potential anti-angina drug to an on-demand oral treatment for erectile dysfunction (Viagra), and more recently to a new orally active treatment for pulmonary hypertension (Revatio)" (Ghofrani et al., Nature Reviews Drug Discovery, 2006). The story is told in how was Viagra discovered? and what was Viagra's original purpose?

When did Viagra reach Australia?

Viagra 25, 50 and 100 mg tablets were entered on the Australian Register of Therapeutic Goods on 4 September 1998 (ARTG search). When it was first launched elsewhere is covered in when was Viagra introduced to the market?

When did generic sildenafil arrive?

Today sildenafil is sold under its generic name as well as the Viagra brand: "Other brands of the same medicine are also available" (healthdirect — Sildenafil (Viagra)). In Australia every one of them is prescription-only. The United States question has its own page: is generic Viagra available in the USA?

What else is sildenafil used for?

High blood pressure in the arteries of the lungs (pulmonary arterial hypertension), as Revatio 20 mg tablets (EMA — Revatio). That use, and the research-only claims, are covered in our guide to lasting longer and other uses.

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