Tylophora leaves are obtained from Tylophora asthmatica, Wight and Arnott (N.O. Asclepiadeae), a twining shrub growing in India, Ceylon, and the Moluccas. The leaves are collected and dried. The leaves are yellowish-brown in colour, 5 to 12.5 centimetres long, and 18 to 65 millimetres broad. They are broadly ovate, and usually cordate at the base. The apex is shortly acuminate, and the margin entire. The upper surface is glabrous, but the lower bears slender, 3- to 5-celled hairs. The leaves, which are somewhat tough have but slight odour or taste.
Constituents.—The chief constituent of tylophora leaves is the crystallisable alkaloid tylophorine, which is soluble in ether; the leaves are also said to contain an emetic principle and about 15 per cent. of mineral matter.
Action and Uses.—Tylophora leaves are official in India and the Eastern Colonies for use as an expectorant and emetic in place of ipecacuanha.
Dose.—3 to 12 centigrams (1/2 to 2 grains); as an emetic, 1 to 2 grammes (15 to 30 grains).
The British Pharmaceutical Codex, 1911, was published by direction of the Council of the Pharmaceutical Society of Great Britain.