Antidote Anecdotes: Medieval Poison Prevention: Medieval Poison Prevention and Cures

by Lady Katja Davidova Orlova Khazarina

In the course of studying herbalism to discover ways Medieval people cured common ailments with plants, I stumbled upon various methods of causing serious harm with the same. The following is a survey of the various poison prevention and curative techniques I found in medieval resources. Some methods are quite logical and effective if viewed from the standpoint of modern medicine, such as avoiding eating potentially poisonous food in the first place by using a taster or by using emetics to purge the poison if ingested. Some methods seem useless and downright silly by modern standards – the use of crushed gemstones or special “feast gear” to neutralize the poison.

This information is related for scholarly purposes only and should not be used as a basis for medical prescriptions. This paper is NOT intended to inspire gentles to test these methods on their neighbors, nor is it a substitute for calling 911!

Methods for Poisoning
According to the 1933 Oxford English Dictionary, poison is "any substance which, when introduced into or absorbed by a living organism, destroys life or injures health; popularly applied to a substance which destroys life by rapid action, and when taken in a small quantity." The same source describes an antidote as "a medicine given to counteract the action of poison, or an attack of disease."

Poisoning – and the search for poison cures – has a long history. Archaeologists have unearthed examples of both in ancient Sumerian, Egyptian, Greek, Asian, and Middle Eastern cultures, according to Dobelis's Magic and Medicine of Plants.
Predominantly, it is believed to have been used as a political tool to remove one's foe or adversary; this theory is based on the fact that both myth (the Egyptian gods Horus and Ra were fatally poisoned) and history (numerous Greek and Roman scholars and emperors were supposedly felled by poison) reflects this.

Why was poisoning such a popular way of offing one's adversaries? Because both the methods and the list of poisons themselves were numerous, the implementation could be very easy, and the action was often difficult to detect – a subtly poisoned drink was generally much harder to trace to its source than a crossbow bolt in the back, according to a wonderfully detailed article on period poisoning by Gunnora Hallakarva.

A medieval poisoner had a variety of choices: deadly herbs (henbane), toxic mushrooms (death angel) and other deadly foodstuffs, animal venom or fluids (snake venom, rabid dog saliva), heavy metals and minerals (such as mercury), and other plant-derived poisons (ergot fungus growing on rye and other grains). Terence Scully, a noted medieval food historian, has written several books on English and French Middle Ages cooking which support this.

"In actual fact a person intent upon poisoning another person in the Middle Ages had a good variety of poisons at hand to draw upon -- what we might well consider an 'embarras de choix.' There was the very common poison obtained from monkshood or wolfsbane; hemlock, the umbelliferous plant (not, of course, the variety of spruce), yielded just as potent a poison as in Socrates' day; black hyoscyamus from the herb henbane, could be relied upon by any poisoner, as could thorn apple; and those dear old stand-bys, arsenic, mercury, and antimony sulfide could be sprinkled or diluted or spread with dependably efficacious results. It was quite understandable if the sundry resources that were available to the potential poisoner might make the object of his plotting somewhat anxious." [Scully]

The simplest method, according to the 12th Century physician Moses Maimonides, was to add a single or compound poison to a highly spiced and/or chopped dish or in a victim's glass of wine; the rather logical assumption is that the strong flavors and uneven texture would mask the bitter taste and consistency of the poison. More imaginative ways, according to Baron Hamish in his entertaining UWEKAT lecture, included fumigating or soaking a victim's clothing with or in poison, applying poison to one's flatware or goblet, and hiding the poison in a pomander ball. Scully's books support these practices, and a French medieval cook's procedures for preventing poison are outlined further below.

“The possibility of food poisoning was a constant worry that was never far from the consciousness of any potentate of the period, or of those who were responsible for his safety. Quite soberly Platina credits the mythology that had grown around this problem and was illustrated by the remarkably long-lived and seemingly unconquerable enemy of Rome, Mithridates the Great: "Pompey the Great, after he had conquered Mithridates, found a composition in his writing desk written in his own hand in which he maintained that he was safe and secure against all poisonings for the whole day if he took one walnut, two dried figs (the most potent antidote), twenty leaves of rue and a grain of salt, all ground together and eaten on an empty stomach." [Scully] (Note: Platina refers to the author of the 14th Century Italian health manual, De Honesta Voluptate, or On Honest Indulgence.)

The Argument for Intentional vs. Accidental Poisoning
Now, some of this poisoning may not have been on purpose. Often, it may have been done with the best intentions to cure someone! During this time period, doctors such as Paracelsus (a Swiss 1500s physician) “advocated the use of metals, such as mercury and antimony, until then used almost exclusively as external medications. Unfortunately, many of those who later prescribed metals (and other dangerous substances) for internal use failed to remember the care and caution with which Paracelsus measured and administered the doses of medicine he gave patients. ‘It depends only upon the does,’ Paracelsus wrote, “whether a poison is a poison or not... A lot kills, a little cures.’” (Dobelis)

In addition, herbs were commonly used as disinfectants and insecticides during this time period – the frequency of which increased the chances of a person or pet getting unintentionally poisoned. Favorite herbs for this purpose, according to Freeman's Herbs for the Medieval Household, were aconite (often called monkshood), black hellebore, and larkspur.

“Albertus Magnus, the 13th Century theologian and scientist, also recommended planting rue among the other plants in a garden so that its powerful smell would discourage harmful vermin," according to Bayard's book Sweet Herbs and Sundry Flowers. "Ointment made of the seeds of stavesacres (a relative of larkspur) was used to dispel head lice; wormwood and rosemary were laid with clothes as moth repellants; pennyroyal was scattered around homes to drive away fleas; and one book recommended the smoke of burning southernwood to drive snakes out of the house. Pastes made of the powdered roots of aconite and hellebore, which contain deadly poisons, were made into preparations to use against larger pests – rats, wolves, and foxes. On occasion, these poisons must have been used on people, too, for Walahfrid Strabo wrote that if a wicked stepmother poisoned your food with aconite, whorehound would counteract it.”

Scully points out that there was also poisoning from stagnant or polluted water, animal bites, the spread of disease from plague and warfare, and occasional unsanitary cooking practices or food. (Official Katja Rant/Tangent #37: No, they didn’t eat rotten meat!!!!!!)

"Food poisoning could, of course, be entirely accidental -- as, for instance, might result from the occurrence of mycobacteria on damp grains, particularly rye -- and infect anyone quite inexplicably and mortally. The pathology of such an infection was totally unknown at this time, of course. Certainly better known were the dangers posed by what were generally called 'poisonous animals.' Such venomous creatures seem to have been ubiquitous; rabies was common enough, and recognized, but the deep forests and lonely corners of Europe abounded with animals whose bites were certain to bring about horrendous suffering and death. The learned Aldobrandino of Siena transmits, for instance, helpful hints about the virtues of onion and garlic in this regard. According to him, onions are much better used in therapy for sickness than as a food for the onions are very effective against the bite of a mad dog or of any other venomous beast. Garlic, likewise, counts among its many potent qualities the ability to heal the bite of a venomous animal; so widespread are its virtues as an antidote to the harmful nature of other foodstuffs, he tells us, that it is called the Triacle de vilains (the Peasant's Treacle, or universal remedy against poison). Toward the end of the Middle Ages still, in Platina alone the attentive reader could find more than a dozen articles of food that are efficacious agents against the bites of poisonous or rabid animals." [Scully]

Medieval Medical Knowledge of Poisons
Dealing with poisoning, whether intentional or not, appears to have been at least a fairly serious if not common concern for medieval doctors; “The seventh medical work of Maimonides is his Treatise on Poisons and Their Antidotes. It is one of the most interesting and popular works because it is very scientific and modern in its approach and was, therefore, used as a textbook of toxicology throughout the Middle Ages.” [See Rosner's survey of Maimonides' writings under Period Resources.]

"What complicated any understanding of the problem of poisons and antidotes immeasurably was the influence of an enormous folklore that originated in antiquity, and undoubtedly long before. This complex body of knowledge concerned the innate powers of all natural things including foodstuffs. One could avail oneself of many specific counteractives that old wives or learned physicians had discovered in a wide variety of animal, vegetable, and mineral products. The consequent difficulty that became clear, however, was that, by eating, one was apt also to expose oneself to the potentially dangerous action that any particular foodstuff could exert. Because an understanding of such potency was vitally important -- the health and well-being of virtually every individual depended upon a comprehensive understanding of it -- this broad and highly detailed lore was faithfully transmitted and constantly amplified by a series of encyclopedists throughout the Middle Ages. Much of what it said belonged naturally within the purview of the professional cook and had to be clearly grasped by him." [Scully]

As example, Virgil wrote highly of Dittany of Crete: "The herbe is of so gret vertu that he dryeth and puteth out yren (iron) out of the body. Therfore bestis ysmyten (smitten) with arwes (arrows) eten therof & dryeth the iren out of the body; for this herbe hath a maner might of were to dryve out arowes & dartes & quarelles, as Ysider seith." (Referring to Isidore of Seville, 6th Century.) Centuries later, Charlemagne listed the herb in Capitulare, his 9th Century edict of required plants for his royal garden ( Hildegarde of Bingen noted the herb in her 12th Century Physica and Gerard praised in his 16th Century Herball.

I found numerous theories and methods for avoiding poisons in medieval sources. As stated before, these range from the commonsensical to the outrageous. I initially started this paper intending to look only for herbal cures – that being my bailiwick – and was surprised by the range of what medieval people thought would cure them…

1. Avoiding Unfamiliar or Suspected Food
Common sense says that if one suspects one's host of deadly intentions, one is cautious about eating one's dinner! Foods with uneven textures, like soups and stews, or those with strong flavors were prime targets for hiding pungent poisons, as I said earlier of Maimonides' writings, so worried diners frequently viewed them with some trepidation.

"As for food of irregular taste such as bitter food, acid, sour, and the like, and any food giving off a bad odor,” wrote Maimonides, “nothing should be partaken of them without prior examination of their reliability... Care should also be exercised with regards to foods common in these parts (Moorish Spain)... obviously sour, pungent, or highly-flavored, also ill-smelling dishes... or those prepared with onion or garlic. All these foods are best taken from a reliable person, above all suspicion, because the way to harm by poison is open only to those foods which assimilate the poisonous taste and smell, as well as the poison's appearance and consistency... The proper defense against such mechanisms is to eat only from the hand of him in whose services one has the greatest confidence. The trick is easily done by mixing the poison with wine, because the latter as a rule covers up the poison's appearance, taste, and smell, and speeds it up on its way to the heart. Whoever drinks wine about which he has reason to suspect that someone has tried to outwit him is certainly out of his mind."

2. Tasters
Of course, you had to eat sometime -- avoiding suspect dishes only works for so long if you are visiting another manor or the Court. Thus, the nobility and royalty frequently employed people to taste their food for them and thus have them run the risk of being killed in their stead. The food was considered safe when the taster sampled a dish and seemed to be no worse for the wear after a certain period of time. Naturally, as His Excellency Hamish pointed out, this could be negated by slow-acting poisons or ones which required repeated doses to be effective. (
See Procedure for Avoiding Poisoning at Feast)

3. Special Dishes
What if you were a guest and if avoiding eating the meal or employing a taster was politically unwise or inconvenient? You probably drank out of a goblet made of “Venetian” glass, which popular belief said would explode if filled with poisoned liquid. Or, maybe you used a "unicorn's horn" as your drinking vessel, since the mythic beast's purity would obviously neutralize any poison. You probably ate your dinner off plates and bowls and used flatware, all of which were coated with or made from some mysterious substance which would react to poison by changing color. [Hallakarva]

“In an age when accidental poisonings probably occurred far more often than paranoid grandees believed they were subject to deliberate poisonings, the cook simply had to earn something close to the total confidence of his master. It is true that a series of tests were normally in place to “prove” each of the dishes and each of the articles of food that would be set before a noble. If the precious unicorn horn – which was usually just a piece of narwhal tusk, though who cared, provided it worked – failed to become discolored or to exude sweat in the presence of poisoned food, then the human taster-tester most surely would do so. This second means of testing the purity of food would undoubtedly exhibit other signs as well that the food was not altogether salubrious.” [Scully]

4. Gemstones, Bezoars, and Toadstones
If you didn't have special feast gear, you might have had a special ring which contained a gemstone, bezoar, or toadstone. By waving this over your food or dipping it into your drink, you would surely neutralize any lurking poisons. Emeralds and amethysts were ascribed magical powers. Besides using rings set with these gemstone, nobility would also grind them into a powder and add this to their food. Larger gemstones were carved into drinking cups and used to combat poisoned beverages. [Rodhe's The Old English Herbals] The gallstones and hairballs from animals' digestive tracts were also ground, set in rings, or simply placed in a goblet by the same reasoning.

5. Amulets and Talismans
The methods above were likely restricted to the nobility, leaving the masses to find cheaper techniques. Much of these prevention methods were based on religious beliefs and folk myth, as Scully wrote. Dating from ancient Jewish and Saxon practices, amulets and talismans were used as protection against many things, not just poisons. An amulet was usually a piece of parchment inscribed with a blessing, while a talisman was generally an object which was blessed by a cleric. Alternatively, it could be something which was believed to be lucky or protective in of itself, such as a four-leafed clover. The Druids supposedly used vervain for such practices, while the Romans touted betony's abilities, according to Dobelis. Gerard described hanging garlands of pennyroyal over doorways as a form of protection and having children wear necklaces made of peony root beads.

6. Charms and Prayers
Not all forms of prevention were tangible objects. Prayer, whether Christian or Pagan, was the common way for the common man to avoid death by poison or venom. “The feastday of St. John the Evangelist (December 27) was associated with wine because a legend held that by blessing a glass of wine that saint rendered the poison in it harmless.” [Scully]
Chanted charms were believed to transfer the poison elsewhere, as in the following Cornish charm from Rodhe’s book:
  "Tetter, Tetter, thou hast nine brothers.
  God bless the flesh and preserve the bone.
  Perish thou, tetter, and be thou gone.
  Tetter, tetter, thou hast eight brothers."

7. Fumigation
The use of incense and smoke to purify a place dates back to Biblical times and continued into the Middle Ages. Dobelis says that common plants used included cypress, fleabane, St. John's wort, hassuck grass, and fennel.

Okay, there were all sorts of ways to avoid being poisoned. So, what would a noble or commoner do if their prevention failed? How did a medieval physician treat poison victims?

1. Vomiting
Just as today, the treatment for non-corrosive poisons was to vomit the poison as quickly as possible. Emetics such as asafetida, cabbage seed, and fig tree ashes were used, as were warm or oily items like milk, butter, or water steeped with emetic or soothing herbs (to settle the stomach lining). Gervase Markham's Good Hus-Wife has several herbal emetic recommendations: “If you would compel one to vomit, take half a spoonfull of stone-crop, and mixe it with three spoonfull of white wine, and give it to the party to drink, and it will make him vomit presently; but do this seldom, and to strong bodies, for otherwise it is dangerous.”

Further, Markham recommends for venom bites: “take Sage and bruise it wel and apply it unto the sore, renewing it at least twice a day, but if it be inwardly, then let the party drinke the iuyce of Sage eyther in Wine or ale morning and evening.”
2. Herbal "Simples"

Alternately, various herbal medicines were employed to counteract the poison or venom. Certain ones were commonly used for certain toxins: mulberry leaves boiled in vinegar to combat henbane, garlic for serpent's bites, frankincense for hemlock. Several were believed to be panaceas to cure any poison, such as fennel seeds boiled in wine, mugwort, mallow, meadowsweet, lovage. Oddly enough, some extremely toxic plants (rue and mistletoe among them) were considered to be effective antidotes. One assumes that the physician who used these toxic plants heeded Maimonides’ precautions about amounts!

3. Prayer
Once again, the power of magic or prayer, depending upon one’s viewpoint, was believed to cure ailments. The Goodman of Paris instructed his young bride to use aconite to slay stags and boars, which makes a lot of sense, but gave her the following advice for dealing with poison or venomous bites of dogs and other “mad beasts”: “Take a crust of bread and write what follows: +Bestera +bestie +nay +brigonay +dictera +sagragan +es +domina +fiat +fiat +fiat+.” [Le Menagier de Paris]

Procedure for Avoiding Poisoning at Feast

The heavy burden of preventing poisoning appears was spread amongst a veritable platoon of servants, from the head cook to the lowliest server, each with the responsibility for specific and often repeated steps for ensuring that their liege lord did not succumb to a poisoning attempt. In The Art of Cookery in the Middle Ages, Scully describes a lengthy process for ensuring the master's food was safe…

"Everything that was intended for the prince's mouth became subject normally to two general sorts of tests, called assays: on the one hand, a test by means of a unicorn horn, and on the other, a test by what vulgarly we might today call guinea-pig experimentation. This second sort of test needs no long explanation: it derived from the principle that one should oneself be willing to stand the salubrity of what one offers to others while making the claim that it is perfectly harmless….Clearly the test assumed that any poison effective enough to do in the prince -- merely harming him could very readily prove in short order to be fatal to the poisoner instead! -- would become manifest quickly and plainly enough to spare the prince the danger of ingesting it."

"The first variety of assay, that which involved the use of a unicorn horn, was more curious, perhaps because the way it operated was somewhat less obvious than the guinea-pig variety of test….The Greek physician and imaginative historian, Ctesia of Cnidus, as the end of the 5th Century BC, wrote, concerning a contemporary practice in India, that "Those who drink from these horns (of unicorn), made into drinking vessels, are not subject, they say, either to convulsions or to the falling sickness (epilepsy). Indeed, they are immune even to poisons if, either before or after swallowing such, they drink water, wine, or anything from these beakers."

Scully further writes that, of course, unicorns weren't terribly common on medieval European estates for some ODD reason… but that didn't stop a priest, while on pilgrimage to the Holy Land, to describe how he'd seen a unicorn purify a polluted river after touching his horn to the waters. And other travelers claimed that knives carved from unicorn horns would sweat, change color, and shake in the presence of poison!

"Regular assays of both sorts, by contact with the unicorn horn and by the ingesting of test samples, were conducted extensively at several stages before anything edible was set down in front of the prince. Even before the prince came to the table, the Linen-Keeper and Hall Porter had to do an assay for poison on the tablecloths by passing the unicorn horn over them. Both the tapestry which the Hall Usher unrolled onto the prince's bench and the cushion on which he was to sit were similarly tested. The most important element awaiting the prince on his table was the salt… Conducted into the hall by the Hall Usher, the Pantler directed the Hall Porter, who then followed him, where to set the large salt dish; there the Pantler removed the lid from the salt dish and with the lid -- in order not to contaminate the salt -- picked up a sample which he passed to the Porter to taste. If the results of the test were satisfactory -- and one can only assume this meant that the Hall Porter remained hale and hearty -- the Pantler took a knife and with it transferred some of the salt from the large salt vessel into the prince's personal salt boat; the Pantler himself made an assay of this salt in the boat, and set it at the prince's place, together with other items also borne in by the Porter…"

Scully describes in detail how the prince washed his hands in a basin of water which was tested twice by the unicorn horn, and how even the towel used to dry his hands was tested for poisons. Also in on the multiple-step testing process were the Pantry Porter, the First Master of the Household, the First Chamberlain, the and the Saucer, as well as several Pages and Serving Valets. Each of the serving dishes was tested, as well as samples of the food placed on or in them. This included the trencher breads at the beginning of feast and the box of dragees (candied seeds) at the end of the meal.

"This complex sequence of tests, or some variant of it, was deemed absolutely necessary to ensure the welfare of any noble in the late Middle Ages. Ultimately, the principle was one of accountability: those who prepared and served food for their master must be willing to be accountable for its wholesomeness; they must vouch with their lives for their fidelity in the service of their master."

Famous Poisons
The great triumvirate of medieval poisons was belladonna, monkshood/wolfsbane, and foxglove. Interestingly enough, not only were they commonly used as poisons, but were also listed in nearly every witch's "flying ointment" recipe - probably because of the hallucinogenic properties of such a combination.

Belladonna, a paralytic, causes people to fall asleep -- usually permanently. It is believed to be the herb which Shakespeare's Juliet used to fake her death and which Macbeth used to quell his enemies. I have not found in my researching any cure for belladonna poisoning. On the other hand, belladonna (or more specifically, the medicine Atropine which is derived from belladonna) is a modern cure for foxglove poisoning.  And Digitalis, the heart medication now derived from foxglove, is a treatment for monkshood, or Aconite, poisoning. (Shakespeare supposedly based Romeo's fatal draught on Foxglove.)

Period Sources
The Closet of the Eminently Learned Sir Kenelme Digbie, Knight… Opened, 1669
Dioscorides, De Materia Medica, 1st Century Greek
John Gerard, The Herbal, or Generall History of Plants, 1597
Hildegard of Bingen, Physica, 12th Century German
The Leechbook of Bald, 10th Century Saxon
Rabbi Moses Maimonides, Treatise on Poisons and their Antidotes, 12th Century
Gervase Markham, The English Hous-Wife, 1649
Le Menagier de Paris (The Goodman of Paris), 1390
Tacuinum Sanitatis (The Medieval Health Handbook), 1400s

Modern Sources
Anderson, Frank J., An Illustrated History of the Herbals, 1977.
Bayard, Tania, Sweet Herbs and Sundry Flowers: Medieval Gardens and the Gardens of the Cloisters, 1985.
Culpeper, Nicholas, Complete Herbal & English Physician, Enlarged, 1814 (based partly on Gerard)
Dobelis, Inge, Magic and Medicine of Plants, 1986
Freeman, Margaret, Herbs for the Mediaeval Household for Cooking, Healing, and Divers Uses, 1943
Grieve, M., A Modern Herbal, 1931 (based on Gerard, etc.)
Hallakarva, Gunnora, The Silent Weapon: Poisons and Antidotes in the Middle Ages, HTTP://
Baron Hamish’s lecture, Poisoning for Fun and Profit, 1994 UWEKAT
Murray, Michael T., The Healing Powers of Herbs, 1992 (a naturopath's analysis of several medicinal plants from a pharmacological and chemical standpoint)
Rohde, Eleanour Sinclair, The Old English Herbals, 1922
Rosner, Fred, Medicine in the Mishneh Torah of Maimonides, 2000
Scully, Terence, The Art of Cookery in the Middle Ages, 1995
Scully, Terence, Early French cookery: Sources, History, Original Recipes and Modern Adaptations, 1995
Stary, Frantisek, The Natural Guide to Medicinal Herbs and Plants, 1998.

I also recommend reading Ellis Peters' Brother Cadfael mystery series (especially Monks Hood and A Morbid Taste for Bones). Her books mention over 78 different herbs used in medieval Europe for medicine, which Peters’ discerned from Gerard and the Leechbook.

I've recently purchased a fascinating book on Anglo-Saxon medicine, Stephen Pollington's Leechcraft: Early English Charms, Plantlore and Healing. It contains several period cures for poisoning, but I have not fully read it at this time.

AEthelmearc War Practice, May 2001
©2001 Chris Adler
Chris Adler