5 of History’s greatest (accidental) medical breakthroughs

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Paradoxically, perhaps the only thing we can be certain of in life is that things rarely go according to plan; and, as history has shown, this has often been the case when it comes to innovations in medical science.

Many of the discoveries which have completely revolutionized the way we practice medicine have in fact come about unintentionally, or by accident.

Contrary to what you might think, these discoveries weren’t all made before the modern era; for instance, Viagra could be said to fall into the category of an ‘unintentional breakthrough’ as it was originally developed with a purpose other than erectile dysfunction in mind, wasn’t developed until the 1990s.

Following on from our recent discussion with Mail Online on the subject, we thought we would delve a little deeper into some of those breakthroughs said to have arisen from less-than-expected origins.

The Treadmill

One of the most essential instruments one will find in the gym today, the treadmill concept has its origins in agriculture and later went on to become part of the British penal system.

Early interpretations of the treadmill, or ‘treadwheel’, constituted a turning circular platform on a vertical axis, which would be powered by an ox or a person pushing a horizontal bar, and used to power a mechanism to grind grain or pump water.

Later, this was developed into a contraption resembling a hamster wheel, which could be powered by a horse.

The story goes that: it was during the earlier part of the 19th century when Sir William Cubitt reputedly had the idea of placing a similar device, akin to an endless staircase, in Bury St Edmunds gaol. Inmates would be made to walk on the device in shifts, which would last for six to ten hours.

Like its earlier incarnations, the treadmill would be used as a tool to grind grain, thereby supplementing the output of nearby mechanical devices such as windmills. However, this purpose was secondary, with punishment being the primary function.

The treadmill was adopted in the 1950s by two American scientists as a diagnostic instrument, used to measure the cardiovascular health of patients. A decade later, events would take place which would propel the device into the fitness industry.

During the late 1960s, a book by Dr. Kenneth Cooper came to prominence among medical theorists. The title of this book was Aerobics. What this book suggested was that a person could vastly improve their cardiovascular health by running a mile in eight minutes, four to five times per week.

Inspired by Cooper’s theory, William Staub, an engineer from New Jersey, recognized the potential of the treadmill as a tool of convenience. He would make it into the exercise machine of choice for those who wanted to walk, run and jog indoors.

The PaceMaster 600, developed by Staub, was the first treadmill designed to be used at home.

Perhaps a fitting testament to the usefulness of the treadmill is Staub himself. He is reported to have used the device regularly to stay in shape, doing so right up until two months before his death in 2012 at the age of 96.


Major surgery would barely be possible today without anesthetics. In its various forms, it is used for minor procedures such as dental extractions, all the way up to life-saving operations such as heart surgery.

The story goes that: before the development of anesthetics as a gas, Hanaoka Seishu, a Japanese surgeon, was experimenting with anesthetic compositions made from herbs. He is reported to be the first doctor to perform surgery on a patient under general anesthetic, supposedly in 1804.

However, anesthesia as we know it today (nitrous oxide mixed with oxygen) took its first steps towards development in the 1840s.

Gardner Quincy Colton would go on to practice dentistry as a profession, however, in this particular period, Colton was reputedly working as a ‘lecturer’, providing public experiments (referred to by some as ‘entertainments’) to audiences. At one of these, a volunteer was given a dose of nitrous oxide (laughing gas), and during the demonstration, acquired an injured leg.

The volunteer apparently felt no immediate signs of pain; and upon seeing this, Horace Wells, a dentist sitting in the audience, realized the potential of the gas for his practice.

He subsequently offered himself up as a test subject, to have a tooth removed by his partner while anesthetized with nitrous oxide (applied by Colton). The extraction was a success, and Wells then went on to use this anesthetic procedure on patients in his surgery.


Today, sildenafil is one of the most famous medicines in the world. Since it was released on the market in 1998, there have been over 23 million prescriptions issued for the drug worldwide.

However, Pfizer originally developed sildenafil as a drug for angina and high blood pressure.

The premise behind angina drugs is similar to those used in erectile dysfunction, in that they work by relaxing circulatory muscle walls and facilitating better blood flow.

Upon testing the medication at a hospital in Swansea, the subjects presented little in the way of improved symptoms for these conditions; but they did experience firm and lasting erections.

The direction of research for Viagra was then altered, and a few years later it became the first licensed oral tablet treatment for impotence.


Saccharin, aspartame, and sucralose are all, to varying degrees, purported to have their origins in chance.

The story goes that: saccharin was discovered by Constantin Fahlberg, a lab worker under Ira Remsen at the John Hopkins University in Baltimore. He was experimenting with coal tars and upon sitting down to dinner, forgot to wash his hands. The residue had transferred to his food and produced a sweet taste.

He (with Remsen’s assistance by some accounts) later developed this substance and named it saccharin.

Aspartame was discovered in the 1960s by chemist James Schlatter. He was attempting to develop a type of treatment called a peptide. It would encourage the stomach to produce more acid and help to treat ulcers.

It was when Schlatter was licking his fingers to turn a page with the substance (once again) on his hands that he discovered the sweet taste. This would develop into aspartame, which would eventually go on to be used in products such as Canderel and Nutrasweet.

Sucralose was discovered in a Tate and Lyle factory in 1976, during research into industrial sugar uses. The sugar substitute which would become known in later years as Splenda was detected by a lab worker who was instructed to test it. He misinterpreted this instruction as one to ‘taste’ it, so he did, and the result was the discovery of a new sweetener variety.

The history of sweeteners is one that is steeped in controversy, but they have nonetheless become a crucial ingredient in diet drinks and cosmetics, as well as in some medications.


Antibiotics are an item we rely on heavily in modern medicine. In addition to treating bacterial infections, they play a vital role in surgery and cancer treatment.

It was in 1928 when Alexander Fleming, a pharmacologist from Scotland, discovered what would go on to become penicillin by mistake.

The story goes that: Fleming was experimenting with staphylococci cultures in his laboratory, and inadvertently left an open petri dish containing one of these by a window.

Returning to the dish, later on, Fleming found that a mold had developed inside it, and had caused the latent bacteria to recede.

Fleming reputedly spent years attempting to isolate this culture and perfect it as a medicine, but had mixed results when trying to convince his peers of the importance of his discovery, or recruit a chemist able enough to assist him.

It wasn’t until part-way through the second world war that penicillin took significant steps towards becoming the mass-produced and available medicine it is today.

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Tom Perry, M.D., attended Tulane University and graduated Magna Cum Laude with a B.S. degree in Parasitology. He received his M.D. degree in 1983 from the University of Virginia School of Medicine, where he gained extensive research experience, including studies conducted through the National Institutes of Health.