One of the best words to describe the evolution of treatment for erectile dysfunction is serendipity.

The idea of serendipity is where something fascinating, useful or valuable is discovered purely by chance. The treatments for ED we have today exist due to a series of exceptionally happy accidents.

It can be difficult to imagine, given how much easier it is to order sildenafil online than the earlier pumps and injections used to be, but the discovery of the drug more commonly known as Viagra exists due to a series of exceptionally happy accidents and drug repositioning exercises.

  1. How Hard Is It To Discover New Medicines?

The discovery of new medical compounds is an exceptionally lengthy, thankless and often fruitless task. According to a report by Eastern Research Group, despite taking over a decade to find a new drug, the success rate of its development is barely 2 per cent.

It is an exceptionally complex process that begins with isolating a new compound and seeing how it interacts with different cells, chemical compositions and enzymes.

Such was the case in Sandwich, Kent, in the late 1980s. In this small town, with a population of fewer than 5,000 people and a claim to fame that its former Earl, John Montagu invented the eponymous food, Pfizer have a major research laboratory that was looking at a rather unique hypothesis.

  1. The Enzyme That Changed Men’s Health

PDE5 was an enzyme that was initially isolated from a rat’s lung in 1980 and was found in a huge number of tissues in the body and organs, and a team at Pfizer in Sandwich had the belief that they could create medicine that blocked PDE5 selectively, which would relax smooth muscles and open blood vessels.

The aim of this was to treat angina, a chest pain that whilst not always life-threatening can be exceptionally unpleasant and undesirable, by expanding the blood vessels around the heart and reducing the pressure on the vital muscle.

Around this time, whilst there was an excitement surrounding the potential of treatments related to PDE5, most were somewhat sceptical it would produce much of an effect.

Indeed, whilst a selective PDE-5 inhibitor was developed that was very powerful and did expand the blood vessels of the healthy volunteers used as part of the trial, it had such a short lifespan in the bloodstream that three pills would be needed a day to keep the effect.

Taking three full doses of sildenafil in a day is not entirely recommended, and indeed many of the volunteers reported sore muscles.

However, that was not the only side effect discovered, as male volunteers noted increased erections days after the dose, which at the time was initially discounted as the effect took too long to be useful as a product.

That changed however when more studies showed increased erections, and it was found that angina amplified the effect of what was the standard treatment for angina at the time: nitrites. This meant that accidentally taking both could lead to dangerously low blood pressure.

This led to the purpose of the studies changing to focus on its potential as an ED medication, with patients with the condition showing its potential effectiveness. Once this hypothesis was starkly proven, it would move on to its larger clinical trial stage, bolstered by publicity about the ED treatment.

The rest, as they say, is history.