How a weird medieval remedy made of garlic, onion, wine and bile could actually turn into effective modern medicine

The Dark Ages aren’t exactly thought of as a time for medical advancement. While some treatments verging on medieval torture, like that scene in The Princess Bride (above), if you take away the cow dung and toad vomit lozenges, not everything was snake oil.

Medieval treatments that work sound oxymoronic. They come from an age infected with superstition, when people were convinced things like demons and dark magic as causes of illness. However, a team of scientists from the University of Warwick recreated a thousand-year-old salve that shows promise in killing bacteria which could otherwise be lethal. “Bald’s eyesalve” comes from the pages of the medical text Bald’s Leechbook (leeches were a hot commodity in medicine back then). This concoction of garlic, onion, wine and bile might sound random—but it could eventually be used to treat the untreatable.

“Understanding the relationship between combinations of natural products and antimicrobial activity may generate a novel way to create new antibiotics from botanicals,” said Jessica Furner-Pardoe and Blessing Anonye, who recently published a study in Scientific Reports. “Bald’s eyesalve [is] an example of an “ancientbiotic” that requires the combination of all ingredients for potent activity against a panel of clinically important bacterial strains.”

Bacteria keep getting more and more resistant to antibiotics. They can be free-floating, but are much more effective when they grow together in masses known as biofilms. What team especially wanted to see how effective Bald’s eyesalve was against pathogens such as strep and staph. Along with other gnarly bacteria, they can be found in often antibiotic-resistant biofilms in diabetic foot ulcers, which can mean amputation to prevent avoid blood infection. Even if they are obliterated for a while, they usually make a comeback. Biofilms are getting harder to take down. This is why the team felt it was most important to test the medieval medicine against biofilms as opposed to bacteria that were just meandering around.

The salve was tested against both free-floating bacteria and biofilms, and unsurprisingly killed off the floaters much more easily. Biofilms were more of a challenge. For the experiment, both an environment made to mimic the fluid from wounds such as diabetic ulcers, along with a more lifelike wound environment made of cultured tissue, were recreated.

Even though some medieval remedies worked, you probably wouldn't have wanted to be in the hands of this guy. Credit: 20th Century Fox/Disney

What the team found was that no single ingredient in the salve was any more effective than all the ingredients combined. While each of the ingredients is known to have antimicrobial powers, none were more effective alone than all of them were together. Allicin is a sulfuric compound in garlic that is released when plant tissue is destroyed. While garlic was suspected to be one of the stronger ingredients because of this, isolated allicin was nowhere near the bacteria-killing level that it was when combined with everything else. Wine was another ingredient that was immediately thought to be effective because of the alcohol (you know what they say about booze and a sore throat). Even the ethanol in wine was not enough.

This could mean a problem with the way medicines are developed now, even a thousand years after someone came up with ye olde remedy.

“It could be that the conventional process for developing drugs may miss key aspects of those herbal remedies which could be effective against biofilms,” the scientists said. “Conventional drug development calls for the isolation of single active compounds, whereas historical medicine usually calls for combinations of whole plants (and other natural materials). There is some evidence that whole plant extracts can have stronger biological effects than individual isolated compounds.”

So isolating just one compound from a natural source isn’t always the answer. Too much allicin can be toxic. Everyone knows what too much wine is capable of. Synergy of ingredients can mean the difference between life and death, as the results of the experiment showed. It’s kind of like the Avengers in microbial form. Any one of them would have never been able to destroy Thanos alone, but their combined power was enough to blow him away, even if Tony Stark and the Hulk’s hand did take a tremendous hit. It would have been impossible otherwise.

Medieval medicine is only going to be investigated further after this, but is cow dung really what you need for a toothache? Get thee to a dentist instead.