This section is from the "A Practical Treatise On Materia Medica And Therapeutics" book, by Roberts Bartholow. Also available from Amazon: A Practical Treatise On Materia Medica And Therapeutics
Senna. The leaflets of Cassia acutifolia Delile (Alexandria senna), and of Cassia elongata Vahl (India senna), (Nat. Ord. Leguminosae, Caesalpinaceae). (U. S. P.) FeuiUes de séné, Fr.; Sen-nesblätter, Ger.
Confection of senna. (Senna, coriander-seed, licorice, figs, prunes, tamarinds, cassia.) Dose, 3 j— 3 ij.
Fluid extract of senna. Dose, oz ss.
Infusion of senna. (Senna, 60 grm.; manna, 120 grm.; magnesium sulphate, 120 grm.; fennel, 20 grm.; boiling water, 800 c. c.; cold water to make up to 1,000 c. c. Dose, oz iv.
Sirup of senna. Dose, 3 ss— 3 ij.
The active constituents of senna prove to be a peculiar colloid body, and an acid, to which has been given the name cathartic acid. It has been shown that "cathartate of ammonia possesses, in a concentrated form, the purgative activity of the original drug." Two bitter principles have been obtained from senna—senna-crol and sennapicrin. It contains also a peculiar sugar—catharto-mannite.
The taste of senna is nauseous and bitter. In infusion—the form in which it is most usually prescribed—it is most disagreeable in odor as well as taste. It produces a sense of warmth in the stomach, and causes much flatulence and griping, which may, however, be prevented by combination with aromatics. Its active principles are absorbed, and the milk of the mother taking senna acquires a purgative property. It is a very efficient cathartic, producing copious liquid stools in about four hours. It does not cause inflammation or hypercatharsis, and its purgative action is not followed by intestinal torpor and constipation. It were, therefore, a very safe and serviceable cathartic, if it were not so disagreeable.
The confection of senna is a palatable preparation, and a mild laxative, operating without any disturbance. It is used chiefly to correct the constipation of pregnancy, but it is highly prized by some patients as a remedy for habitual constipation. It is also taken to procure soft and easy evacuations in haemorrhoids, fissures of the anus, etc. A large bolus (one hundred and twenty grains), taken at bedtime, will operate gently on the following morning. The fluid extract of senna is a form for the administration of this drug more agreeable than the infusion. These two preparations are very excellent cathartics to overcome constipation, especially when ordinary purgatives fail.
The action of senna is much improved by combination with other purgatives, and with aromatics. The well-known "black draught" is an infusion of senna with sulphate of magnesia—one ounce of the latter dissolved in four ounces of the former. By the addition of coffee, the odor and flavor of senna may be rendered more tolerable. Two drachms of senna and one drachm of coffee may be infused in three ounces each of hot milk and boiling water, and the whole drunk after twelve hours.