Medieval Medicinal Plants #2

In this second blog on medieval medicinal plants, I’ll talk about leprosy and plague then look at the use of plants in anaesthesia and to treat other conditions.

One disease synonymous with the medieval period is plague, which caused terror throughout Europe.  It had no cure and was believed to be a punishment from God.  The major outbreak in Europe which lasted from about 1346 to 1353, killed up to 50 million people – about 60% of the population.  Early in the outbreak, there were reports of people abandoning stricken family members, including children although later, efforts turned more to prayer.  The best chances of survival were in places operating strict quarantine policies.

A bishop instructing clerics suffering from leprosy from Omne Bonum by 14th-century clerk James le Palmer (British Library, MS Royal 6 E VI, vol. 2, fol. 301ra).

Leprosy was another disease which terrified people.  Believed to affect those guilty of lechery or immoral sex, sufferers were often shunned and exiled to the edge of the town.  We now know it is caused by a severe bacterial infection.

In medieval times it was believed that when you die you entered purgatory, where you paid for all your sins before moving on. Sufferers from leprosy, on the other hand, were paying for their sins early so were already on their way to redemption.  Thus, Christian benefactors could gain from helping lepers and asking them to pray for them in return as their prayers held more weight!

While plague and leprosy couldn’t be cured, there were effective treatments available for some things, including respiratory conditions.

A sweet confection incorporating the juice of horehound (Marrubium vulgare) was used to treat coughs and horehound is used today in herbal medicine to treat asthma and bronchitis.  Marrubiin, one of its constituents has shown a number of medicinal effects including as an antispasmodic and analgesic.

Herbs were also used in medieval anaesthetics taken before surgery, notable dwale which was drunk with wine.

Chemical diagram of lactucin

Dwale contained hemlock, opium and henbane, all of which have pain-killing or sleep-inducing properties.  Wild lettuce was also included – this was a source of lactucarium or lettuce opium, known to make you drowsy (as described by Beatrix Potter in the Tale of the Flopsy Bunnies).  The sedative effects are down to the compounds lactucin and lactucopicrin, also present in the Bach remedy plant chicory.

Wild neep (or bryony) was added – there are 2 suggestions as to what the purpose of this was – firstly, it was a direct replacement for mandrake, used in Middle Eastern recipes, but not available (or too expensive) in northern Europe.  Mandrake was used to improve sexual function of men, so was highly prized (and so expensive). Bryony had similar, fleshy roots and was sometimes known as English mandrake.   An alternative suggestion is that bryony’s inclusion was for its purgative properties, which we now know come from the compound bryonin.


Bryony (Bryonia dioica); image AnRo0002 via wikimedia commons

Hemlock, henbane and opium could all be toxic. Due to the variability in quantity of the active compounds in a given plant even when the mixture was carefully prepared, the effects were unpredictable – it was therefore beneficial to remove the mixture from the body quickly!  Other ingredients in dwale were bile, possibly to speed up absorption, and vinegar.  After surgery, vinegar was dabbed on the face or dill seeds put in the nose to bring the patient round.

Rather than drinking an anaesthetic, so-called soporific sponges could also be used.  These were soaked in a macerated mixture of opium, mandrake, hemlock and henbane.  When the sponge was needed it was soaked in hot water and the fumes inhaled.  Patients not only slept through the operation, but for several hours after, giving their bodies some time to recover from the trauma of surgery.  A sponge soaked in hot vinegar or dill seeds were used to bring the user round after the operation.  These sponges were an early example of inhalation therapy.

So, while knowledge of anatomy and what caused disease was limited, there were treatments available for certain conditions often with plants.  And today, some of these plants  have been shown to have beneficial effects.

Sources: Toni Mount (2016); Medieval Medicine Its Mysteries and Science; Amberley Publishing, ISBN 978 1 4456 5542 0

O.K. Popoola, A.M. Elbagory, F. Ameer, A.A. Hussein (2013); Marrubiin; Molecules, 18(8), 9049–9060;

J. Robertson (2018);

A.J. Carter (1999); Dwale: and anaesthetic from old England; BMJ, 319(7225), 1623–1626; 

Gwenda Kyd (2018); The Plants of Dr Bach; Vervain Publishing