5 Surprising Stories of Accidental Drug Discoveries

It seems as though many great innovations have stemmed from unplanned findings.

The following 5 drugs found their place in therapy by accident. Here are their fascinating stories of discovery.

1. Smallpox Vaccine

In the late 1700s, surgical apprentice Edward Jenner noticed that those who worked with cattle didn’t seem to catch smallpox.

After Jenner became a physician, a milkmaid came to him for treatment of cowpox. He collected material from the milkmaid’s cowpox lesions and used it to inoculate an 8-year-old boy.

Two months later, he inoculated the same boy with material obtained from a smallpox patient. After the boy didn’t develop smallpox, he concluded the boy was immune, and thus the vaccine that eradicated smallpox was born.

2. Lithium

In the mid-1800s, lithium was used to treat gout and bladder stones.

After World War II, psychiatrist John Cade injected urine from healthy and mentally ill patients into the abdomens of guinea pigs. He found that the guinea pigs injected with urine from healthy patients died faster, which raised the idea that more uric acid was in the urine of the mentally ill patients.

In an attempt to increase the solubility of the uric acid, Cade added a lithium solution. Following injection, he noticed that the guinea pigs were sedated and calm rather than excited.

Interestingly, Cade ingested the lithium himself to ensure that it was safe for humans, and he later began administering it to patients with psychiatric disorders.

3. Warfarin

In the early 1920s, veterinarians noticed that particular cattle bled profusely when injured or undergoing procedures. They discovered that these cattle were eating a spoiled clover, and their hemorrhaging was subsequently dubbed “sweet clover disease.”

About 20 years later, researchers at the University of Wisconsin isolated a compound from the plant, which was later marketed as warfarin.

4. Pencillin

In the late 1920s, bacteriology professor Alexander Fleming returned to his messy laboratory after a 2-week vacation. He began sorting through petri dishes containing colonies of Staphylococcus.

On one of the dishes with colonies, he noticed a mold growing with the zone around it being completely clear. The mold was determined to be Penicillium notatum, which excreted a substance later isolated and used therapeutically as penicillin.

5. Botox

In 1820, botulism was first described as a disease arising from spoiled sausage. It wasn’t until the late 1800s that Clostridium botulinum was discovered as the source of this toxin.

In the early 1970s, a group of ophthalmologists specializing in eye muscle disorders were searching for diagnostic technique to evaluate individual muscle contribution to eye movements. They injected the botulinum toxin into the extraocular muscles of monkeys, which induced a confined paralysis of the injected muscle.

In the late 1980s, a plastic surgeon treated facial asymmetry using the toxin, leading to its widespread cosmetic use today.