CotoBotanical Name: Botanical source unknown
Family: Possibly N.O. Lauracea Part Used: The bark.
Description: A bark bearing this name came into the London drug market about 1893. The bark of a rubiaceous plant (Palicourea densiflors), known as Coto, is employed in Brazil for rheumatism, but it is not known if this is the true Bolivian plant; the outer surface is irregular, of a cinnamon brown colour. It is sold in pieces of 4 to 6 inches long, 3 inches wide and about 1 inch thick, and is sometimes covered with an adherent corry surface, free from lichens. The inner cross-sections of the bark are covered with yellowish spots, the odour is aromatic and much stronger if bruised, taste hot and biting; in powdered form the smell is very pungent. This description conforms with the barks sold in the American markets, but other barks are used under the same name, the chief being Paracote bark; this has an agreeable spicy taste, but is not so strong-smelling or tasting, and has deep white furrows on the surface.
Constituents: Coto bark contains a volatile alkaloid, a pungent aromatic volatile oil, a light brown soft resin, and a hard brown resin, starch, gum, sugar, tannin, Cal. Oxalate and three acids, acetic, butyric and formic.
Medicinal Action and Uses: Antiseptic, astringent. Coto bark is irritating to the skin applied externally. If taken internally it gives constant violent pain and vomiting. Its chief use is in diarrhoea, but it has a tendency to produce inflammation, so must be used with great caution, it is said to lessen peristaltic action. Paracota bark resembles it in action, but is much less powerful. In Japan, paracota bark has been successfully employed for cholera by hypodermic injection of 3 grains of paracotoin. The value of cotoin in diarrhcea is established, and it is also used for catarrhal diarrhoea and for diarrhcea in tubercular ulceration of typhoid fever. Has also a specific action on the alimentary canal, dilating the abdominal vessels and hastening absorption.
Preparations and Dosages: Cotoin, 1 to 3 grains. Fluid extract, 5 to 15 drops. Powdered coto, 2 to 15 grains.