'Lactucarium' is the milky fluid secreted by several species of
lettuce, especially ''
Lactuca virosa'', usually from the base of the stems. Lactucarium is known as lettuce
opium because of its
sedative and
analgesic properties. It has been reported to promote a mild sensation of euphoria, but ''Lactuca virosa'' is poisonous
[1], and at least one fatality has occurred during an attempt to use it for intoxication.
[2][3] Because it is a
latex, Lactucarium physically resembles opium, in that is excreted as a white fluid and can be reduced to a thick smokeable solid.
History
"Lettuce Opium" was used by the Ancient Egyptians, and was introduced as a drug in the United States as early as 1799. The drug was prescribed and studied extensively in Poland during the nineteenth century, and was viewed as an alternative to opium, weaker but lacking side-effects, and in some cases preferable. However, early efforts to isolate an active alkaloid were unsuccessful.
[4] It is described and standardized in the 1898
United States Pharmacopoeia[5] and 1911
British Pharmaceutical Codex[6] for use in lozenges, tinctures, and syrups as a
sedative for irritable cough or as a mild
hypnotic (sleeping aid) for
insomnia. The standard definition of lactucarium in these codices required its production from ''
Lactuca virosa'', but it was recognized that smaller quantities of lactucarium could be produced in a similar way from ''
Lactuca sativa'' and ''
Lactuca canadensis'' var. ''elongata'', and even that lettuce-opium obtained from ''
Lactuca scariola'' or ''
Lactuca altissima'' was of superior quality.
[7]
In the twentieth century, two major studies found commercial lactucarium to be without effect. In 1944, Fulton concluded, "Modern medicine considers its sleep producing qualities a superstition, its therapeutic action doubtful or nil." Another study of the time identified active
bitter principles
lactucin and
lactucopicrin, but noted that these compounds from the fresh latex were unstable and did not remain in commercial preparations of lactucarium. Accordingly, lettuce opium fell from favor, until publications of the
hippie movement began to promote it in the mid-1970s as a legal drug producing
euphoria, sometimes compounded with
catnip or
damiana.
[8]
The seeds of lettuce have also been used to relieve pain. Lettuce seed was listed between
belladonna and
snow in order of anaesthetic potency in
Avicenna's ''
The Canon of Medicine'', which served as an authoritative medical textbook from soon after 1000 A.D. until the seventeenth century.
[9]
Contemporary use
Although lactucarium has faded from general use as a pain reliever, it remains available, sometimes promoted as a legal
psychotropic.
The seed of ordinary lettuce, ''
Lactuca sativa'', is still used in Avicenna's native
Iran as a folk medicine, and a crude extract of the seeds was shown to have analgesic and antiinflammatory effects in standard
formalin and
carrageenan tests of laboratory rats. It was not toxic to the rats at a dose of 6
grams per
kilogram[10]
Mechanism
The active ingredients of lactucarium are believed to be
lactucin and its derivatives
lactucopicrin and 11β13-
dihydrolactucin, which have been found to have
analgesic activity equal or greater to that of
ibuprofen in standard hot-plate and tail-flick tests of sensitivity to pain in laboratory mice. Lactucin and lactucropicrin were also found to have
sedative activity in measurements of spontaneous movements of the mice.
[11] Some effects have also been credited to a trace of
hyoscyamine in ''
Lactuca virosa'', but the alkaloid was undetectable in standard lactucarium.
6
Formulations
Lactucarium was used unmodified in lozenges, 30-60
milligrams (0.5 to 1
grain, sometimes mixed with
borax. However, it was found to be more efficient to formulate the drug in a
cough syrup ''(Syrupus Lactucarii, U.S.P.)'' containing net 5% lactucarium, 22% glycerin, 5% alcohol, and 5% orange-flower water in syrup.
6
References
1. Plants for a Future: ''Lactuca virosa''
2. The Straight Dope Cecil Adams
3. [Abuse of lactuca virosa] PMID 12762295, , , , Presse Med. 2003 Apr 26;32(15):702-3,
4. PMID 17153150
5. King's American Dispensary:Tinctura Lactucarii (U. S. P.)—Tincture of Lactucarium Harvey Wickes Felter, M.D., and John Uri Lloyd, Phr. M., Ph. D.
6. Lactuca, Lactucarium the Council of the Pharmaceutical Society of Great Britain
7. King's American Dispensary:Tinctura Lactucarii (U. S. P.)—Tincture of Lactucarium Harvey Wickes Felter, M.D., and John Uri Lloyd, Phr. M., Ph. D.
8. Lettuce opium
9. Avicenna and the Canon of Medicine: a millennial tribute Richard Dean Smith
10. Analgesic and anti-inflammatory activity of Lactuca sativa extract in rats, Sayyah M, Hadidi N, Kamalinejad M., , , J Ethnopharmacology 92(2-3):325-9 PMID 15138019, 2004
11. , Wesolowska A, Nikiforuk A, Michalska K, Kisiel W, Chojnacka-Wojcik E., , , 1: J Ethnopharmacol 107(2):254-8 PMID 16621374,