What is "hyoscyamine"

Hyoscyamine \Hy`os*cy"a*mine\, n. [See Hyoscyamus.] (Chem.) An alkaloid found in henbane ( Hyoscyamus niger), and regarded as its active principle. It is also found with other alkaloids in the thorn apple and deadly nightshade. It is extracted as a white crystalline substance, with a sharp, offensive taste. Hyoscyamine is isomeric with atropine, is very poisonous, and is used as a medicine for neuralgia, like belladonna. Called also hyoscyamia, duboisine, etc.

n. (context chemistry English) an alkaloid, the stereoisomer of atropine, used medicinally to treat abdominal pain and similar conditions

n. a poisonous crystalline alkaloid (isometric with atropine but more potent); used to treat excess motility of the gastrointestinal tract

Hyoscyamine (also known as daturine) is a tropane alkaloid. It is a secondary metabolite found in certain plants of the family Solanaceae, including henbane ( Hyoscyamus niger), mandrake ( Mandragora officinarum), jimsonweed ( Datura stramonium), tomato ( Solanum lycopersicum) and deadly nightshade ( Atropa belladonna). It is the levorotary isomer of atropine (third of the three major nightshade alkaloids) and thus sometimes known as levo-atropine. Hyoscyamine should not be confused with hyoscine, an older alternate name for the related nightshade-derived anticholinergic scopolamine for which it is the precursor.

Brand names for hyoscyamine include Symax, HyoMax, Anaspaz, Egazil, Buwecon, Cystospaz, Levsin, Levbid, Levsinex, Donnamar, NuLev, Spacol T/S and Neoquess.