A few years ago, if you were asked to name a well-known medicine, you may well have said Aspirin or Paracetamol. Today you are just as likely to mention Viagra™.

Even though Viagra™ has only been available since 1998, it has already gained a world-wide reputation, with sales of around £1billion per year. Pfizer, the world's largest pharmaceutical company, has a certain amount of good luck to thank for this phenomenal success.

It was by chance that they discovered its ability to treat erectile dysfunction, having developed it to treat angina. In this electronic resource (e-source), we'll use the Viagra™ story to show how a medicine is designed, developed and produced.

1. Lifecycle of a medicine
2. Concept
3. Discovery research
4. Research and development
5. Trialling
6. Erectile dysfunction
7. Quiz

A glossary of terms: any word with a glossary entry is highlighted like that. Clicking on the word will open a new window with a definition of that word.

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