Viagra's discovery

Viagra's discovery


Even the fastest selling drug of all time, Viagra, is not used for what it was originally intended.
It started life as plain old UK92480, a new treatment for angina, a heart condition that constricts the vessels that supply the heart with blood.
The drug company Pfizer was looking for something that would relax these blood vessels, however its trials in people were disappointing

Pfizer were about to abandon further trials when the trial volunteers started coming back and reporting an unusual side effect - lots of erections.
Pfizer senior scientist Chris Wayman was charged with investigating what was happening. He created a model 'man' in the lab.
He took a set of test-tubes filled with an inert solution, and in each one placed a piece of penile tissue, taken from an impotent man.
Each piece of tissue was then connected up to a box that, at the flick of a switch, would send a pulse of electricity through the tissue.
Applying this current of electricity mimics what happens when a man is aroused.
The first time he did this nothing happened to the vessels. However, when he added Viagra to the tissue bath the penile blood vessels suddenly relaxed - as they would for a man to give him an erection.
He said: "What was amazing about this study was that we saw a restoration of the erectile response. Now we were on to something which could only be described as special".
Before the launch of Viagra in 1998 there was no oral treatment for erectile dysfunction, the only options were an injection or a fairly gruesome prosthetic implant.
Now, thanks to a failed Angina treatment, men had another option. Viagra is now one of the most prescribed drugs in the world.

Horizon: Pill Poppers can be seen on BBC Two on Wednesday 20 January at 9pm or afterwards via BBC iPlayer