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Lactuca serriola, prickly lettuce


Lactuca serriola, prickly lettuce

Lactuca serriola, prickly lettuce

A close relative of the domestic lettuce that has been used as an alternative to opium.


Asteraceae. The name Compositae is sometimes used for this family.

Meaning of the Name


From the Latin, ‘lac’, ‘milk’ after the milky sap in the stems.


From the Latin, ‘serro’, ‘saw’ for the saw-tooth like edges to the leaves.



Common Names and Synonyms

prickly lettuce, compass plant, Lactuca scariola, wild opium

How Poisonous, How Harmful?

Contains lactucarium which is a sedative and painkiller and can be used as a less powerful alternative to opium. Larger doses are reported to be stimulant rather than sedative. Pliny says it is purgative if large amounts are ingested.


Though there are a number of reports of contact dermatitis arising from handling plants in the Lactuca genus these tend to be in people, such as chefs and horticultural workers, who have had prolonged exposure to the plant.

It is widely believed that the high level of nitrates in lettuce can lead to kidney failure in young ducks but the only report available suggests that death of a number of ducklings followed narcosis rather than kidney failure.

Folklore and Facts

Lactuca serriola, prickly lettuce

The prickly underside of the leaves

Hildegard of Bingen calls prickly lettuce a useless plant and says anyone who eats it will become mindless.  She says the related wild lettuce is useful for suppressing desire. A man with excessive lust should cook the lettuce in water and use the water to pour over himself in a sauna whilst having the cooked lettuce wrapped around his loins. Having the genitals wrapped in any sort of limp wet leaves might be expected to reduce desire.

Min, the ancient Egyptian god of sexuality, is often depicted in bas reliefs with a vegetable which was only recently identified as Lactuca serriola. This led to tests which showed it to have an aphrodisiac effect on rabbits.

Leaves on the main stem follow a north south plane and the plant can be used as a compass. It should be said that many plants follow some sort of orientation relative to the sun and/or magnetic poles.

The precise origin of the 'soporific sponge', used to achieve anaesthesia for the performance of surgery, is impossible to determine but one of the first published accounts is found in the 'Antidotarium' of Nicolaus Salernitanus, Nicholas of Salerno, printed in 1470 but which would have to have been written in the 12th century if it is the work of Nicholas. In this recipe, the normally quoted formula of opium, henbane and hemlock is augmented with mulberry juice, mandrake, ivy and lettuce.

A sponge would be soaked in the juice of these plants and then dried to be held in stock until required. Wetting the sponge and placing it over the patient's nose and mouth resulted in the inhalation of the narcotic fumes. It is said that sleep lasting up to 96 hours could be achieved so that the body had the opportunity to recover from the trauma of surgery as well as the patient being insensible during the procedure.