96-2 
Lactucarium, or Lettuce Opium, being of the same nature, no matter from 
what species it is obtained, consists of the inspissated milky juice of various spe- 
cies of Lactuca. The yield varies greatly with the species; greatest in ZL. verosa, 
and diminishing as follows: L. scarioda, L. altissima, L. Canadensis, L. sahiva. Dr. 
Coxe, of Philadelphia, was the first to call the attention of the profession to this 
substance as a substitute for commercial opium;* his reasoning and experiments 
were based upon the product of Z. sativa. Although Lettuce has been considered 
narcotic from ancient times, still it is but slightly soporific, and hardly deserves a 
tithe of the reputation writers have made for it. 
Lactucarium from Z. vérosa is still officinal in the U. S. Phar., but will, without 
doubt, be dropped at the next revision. 
PART USED AND PREPARATION.—The whole fresh plant, just as the blos- 
soms open, is chopped and pounded to a pulp and weighed. . Then two parts by 
weight of alcohol are taken, the pulp thoroughly mixed with one-sixth part of it, 
and the rest of the alcohol added. After stirring the whole well, it is poured into a 
well-stoppered bottle, and allowed to stand eight days in a dark, cool place. The 
tincture formed thus, after straining and filtering, has a deep orange-red color by 
transmitted light; the odor of canned tomatoes; a slightly bitter and astringent 
taste; and an acid reaction. 
CHEMICAL CONSTITUENTS.—Lactucarium, or Thridace, as noted above, 
represents in itself all the active principles of the plant, being a mixture of differ- 
ent organic and about ten per cent. inorganic bodies. It is not fully soluble in 
any vehicle, and merely softens on the application of heat. Subjected to analysis, 
it yields: 
_ Lactucerin,+ C,,H,,0.{—This compound body composes nearly half the whole 
weight of Lactucarium. It forms in slender, colorless, microscopic, odorless and 
tasteless acicular crystals, insoluble in water, soluble in boiling alcohol and cold 
ether, and melting at 232° (449.6° F.). 
_ Lactucin, C,,H,,0,(H,0).—This body, which proves not to be a glucoside, 
gives to Lactucarium its intensely bitter taste. It forms, when purified, white, bit- 
ter, pearly scales, insoluble in ether, soluble in alcohol and in hot water. 
Lactucic Acid.— This very acid body, isolated by Pfaf and Ludwig, results as 
an amorphous light yellow or brownish mass, only crystallizing-after long standing. 
Lactucopicrin, C,,H,,O,,.—This bitter amorphous substance seems to be 
formed by the oxidation of Zactucin. It is soluble in alcohol and water. 
Beside the above, Lactucarium also contains a yellowish-red tasteless resin ; 
a greenish-red acrid resin; caoutchouc; gum; oxalic, citric, malic, and succinic 
acids ; sugar; mannite; asparagin; and a volatile oil. 
* Trans. Am, Philosoph. Socy., 1799, 387. 
+ Lactucon, 
t Fliickiger, C,,1,,0; Franchimont, C,,H,,0. 
