The long sweep of human history is littered with medical experiments that range from the ingenious to the downright bizarre. Among those, the Middle Ages stand out as a time when physicians were caught between the ancient theories of Greek scholars and the powerful grip of superstition and religious doctrine. In this strange crossroads, doctors tried everything from herbal poultices to bone‑binding rituals, producing a mixed bag of successes and spectacular flops.
While medieval scholars were busy gazing at the heavens and consulting astrological charts, they also dared to test new ideas on the human body. The result was a medley of treatments that sometimes leaned on the four humors, sometimes on the mystical power of herbs, and occasionally on plain, gritty practicality. Though many of those remedies look odd to modern eyes, a surprising number actually delivered real, measurable benefits – some of which echo in today’s medical practice.
10 Weird Medieval Practices That Really Worked
10 Skull Knitting
Head injuries were a common and deadly hazard in the medieval battlefield and in brutal street brawls alike. Modern research indicates that individuals who survived a traumatic brain injury in that era faced a roughly 6 % higher chance of an early death compared with those who escaped such wounds.
Field surgeons, pressed to keep wounded combatants alive, resorted to a technique that sounds like something out of a fairy‑tale: they would literally stitch the broken pieces of a skull back together. By weaving the fractured bone, they could stabilize the protective casing around the brain, buying the patient precious time for the body to mend.
Indeed, the practice of “skull knitting” was reserved for the privileged – knights, nobles, and wealthy merchants – who could afford the limited medical expertise of the day. For the many peasants who suffered similar injuries, such sophisticated care remained out of reach.
9 Examination Of Urine
Greek physicians like Hippocrates and Galen taught that illness sprang from an imbalance among the four humors – black bile, yellow bile, phlegm, and blood. Their writings survived the centuries and formed the backbone of medieval diagnostic theory.
Manuscripts from the period instruct doctors to carefully examine a patient’s urine, noting its colour, clarity, and any sediment. Though the humoral theory itself has long been debunked, the underlying observation – that urine can reveal internal disease – was spot‑on.
Even without modern laboratory equipment, medieval physicians could spot signs of kidney trouble, infection, or metabolic disorders simply by the hue of a sample. Dark, cloudy, or blood‑stained urine signalled that something was amiss inside the body.
Today, clinicians still rely on urine analysis as a first‑line diagnostic tool. The same visual cues that medieval healers prized – colour changes, presence of blood, and unusual opacity – remain central to detecting kidney disease and other ailments.
8 Garlic And The Black Plague
The Black Death swept across Europe in the 14th century, leaving a trail of death that seemed unstoppable. Physicians of the time were baffled, lacking any knowledge of bacteria or vectors, and resorted to a bewildering array of “cures.”
Amid the chaos, a simple, pungent remedy emerged: raw garlic. Whether pressed onto open wounds or mixed into concoctions, garlic’s natural antibacterial properties offered a genuine line of defence against the plague‑carrying bacterium Yersinia pestis.
Folklore tells of the infamous “four thieves vinegar,” a mixture of garlic, herbs, oil, and vinegar that bandits supposedly used to protect themselves while looting plague‑riddled towns. While the story is colorful, the underlying ingredient – garlic – does possess compounds that can inhibit bacterial growth.
Modern studies confirm garlic’s potency as a natural antibiotic. In the medieval context, its use may have slowed the spread of infection, granting at least a few victims a chance to survive the otherwise relentless pandemic.
7 Street Cleaning
Before the mid‑14th century, medieval towns treated their streets like open sewers, dumping everything from human waste to discarded food. This filth created a perfect breeding ground for the fleas that carried plague‑bacteria.
In 1349, King Edward III of England wrote a scathing letter to London’s mayor, complaining that the stench of rotting waste was worsening the disease’s spread. Though his understanding of germ theory was limited, the royal admonition sparked a city‑wide push for better sanitation.
The English authorities responded by levying steep fines on anyone caught littering human excrement onto the streets – first doubling, then tripling the penalties compared with pre‑plague levels. This forced citizens to adopt cleaner practices, reducing the environmental reservoir of the plague‑carrying fleas.
While medieval sanitation reforms were crude by today’s standards, they achieved a tangible public‑health benefit: fewer plague cases as the bacteria lost its favorite habitat. In many ways, this early “clean‑up” effort foreshadowed modern infection‑control strategies.
6 Trephination
Trephination – the practice of drilling a hole into the skull – dates back to the Neolithic era and appears in cultures worldwide. Medieval surgeons adopted the method, believing that relieving pressure inside the head could save lives.
To the modern eye, the idea of boring a hole through a living cranium seems absurd, yet the underlying principle is sound: if a head wound causes dangerous swelling or bleeding, creating an opening can lower intracranial pressure and prevent fatal outcomes.
Today, the technique has evolved into the craniotomy, a highly refined surgical procedure used to access the brain for a variety of conditions. Archaeological evidence shows that many medieval patients survived multiple trepanations, suggesting a respectable survival rate for the time.
5 Bald’s Eye Salve
Bald’s Eye Salve, recorded in the ninth‑century Bald’s Leechbook, is a thick ointment originally intended for eye infections. Its recipe blends onions, garlic, a host of spices, and assorted herbs – a classic medieval pharmacy mix.
Modern laboratory analysis reveals that the salve is a potent antimicrobial cocktail. It can dismantle stubborn bacteria such as MRSA, a strain that often evades contemporary antibiotics. Removing even a single ingredient markedly reduces its effectiveness, underscoring the careful balance the medieval healers achieved.
4 Cauterization Of Wounds
Cauterization – the application of intense heat to a wound – was a mainstay of medieval surgery. Whether sealing a battlefield amputation or treating a minor cut, physicians would brand the tissue with a red‑hot poker or heated metal plate.
Archaeological finds show cauterization marks as small as 2.5 cm across, indicating that even modest injuries were sometimes treated this way. The method’s double‑edged nature is clear: it instantly stops bleeding by sealing blood vessels, yet it also denatures proteins, potentially opening the door to secondary infection.
When a patient faced massive blood loss and no other options, cauterization could buy crucial minutes – or even hours – of life. However, the charred tissue could become a nidus for bacteria, making post‑operative infection a serious risk.
Medieval surgeons adapted their technique to the wound’s location, sometimes using a flat heated surface, other times thrusting a glowing rod deep into the injury. The patient invariably had to be restrained while the surgeon worked.
3 The Catheter
When a medieval patient suffered a blocked urinary tract, physicians turned to a crude catheter – a long, pointed metal tube designed to navigate the urethra and clear the obstruction.
The device’s curvature mirrored the natural bend of the urethra, but inserting it required several assistants to hold the patient down while the surgeon forced the instrument upward. The procedure was painful, risky, and depended heavily on the cleanliness of the metal.
Despite its barbaric execution, the ancient catheter did achieve its goal: it restored urine flow. Modern catheters, by contrast, are soft, flexible tubes that gently channel urine out of the body without the need for brute force, illustrating a clear line of evolution from medieval ingenuity to contemporary comfort.
2 Cataract Removal
Cataracts – clouding of the eye’s lens – have plagued humanity since antiquity. In medieval Europe, the only remedy was a swift, blade‑based extraction performed by a barber‑surgeon.
These surgeons, recognizable by the iconic red‑and‑white pole outside their shops, wielded sharp knives to pierce the eye and remove the opaque lens. The procedure required steady hands and a calm patient, as any misstep could lead to blindness or death.
Imagine a 14th‑century villager walking into a bustling barbershop, pleading for sight. The barber‑surgeon, after a quick prayer, would plunge his scalpel into the eye, hoping to restore vision. When performed skillfully, the operation succeeded, though it was undeniably terrifying.
1 Hemorrhoids
Medieval physicians, accustomed to using fire as a medical tool, eventually applied the same principle to the treatment of painful hemorrhoids. By heating a metal poker until it glowed orange, they could cauterize external hemorrhoidal tissue, sealing off blood flow and providing temporary relief.
For internal hemorrhoids, the same red‑hot instrument was sometimes inserted directly into the affected area, burning the swollen veins from the inside out. While effective in stopping bleeding, the method was excruciating and carried a high risk of infection.
Even today, when topical creams fail, modern medicine may resort to laser surgery or infrared coagulation to remove hemorrhoids – a high‑tech echo of the medieval practice of using intense heat to destroy problematic tissue.