Source and Composition. The leaves and tops of Hyoscyamus niger, a biennial plant, also of the order Solanaceae. Its alkaloid, Hyoscyamine, is probably identical with Atropine, Daturine and Duboisine; from it is derived Hyoscine, a semi-liquid alkaloid yielding Tropic Acid and Pseudotropine.
- Extractum Hyoscyami,—Dose, gr. ss-j, if active.
- Extractum Hyoscyami Fluidum,—Dose, ♏v-xx.
- Tinctura Hyoscyami,—15 per cent. Dose, ʒj-℥j, the latter as hypnotic.
- Hyoscyaminae Sulphas, Hyoscyamine Sulphate,—Dose, gr. 1/40-1/20 by mouth; hypodermically should not exceed gr. 1/65. In very urgent cases, gr. ¼-j may be given by the mouth.
- Hyoscinae Hydrobromas, Hyoscine Hydrobromate,—Dose, gr. 1/100-1/50, by mouth or hypodermically.
Incompatible, most frequently prescribed with Hyoscyamus is Liquor Potassae. All the fixed caustic alkalies destroy its alkaloids, as well as those of the allied plants.
Physiological Action. The action of Hyoscyamine is similar to that of Atropine, Duboisine and Daturine, except that it is the least powerful and least irritant of the group, and the most calmative and hypnotic. It is more stimulant to the vaso-motor system and the cardiac accelerator apparatus than is Daturine, but is less active upon the pneumogastric. Its delirium is never furious and is without hyperaemia, but is accompanied by insomnia. Hyoscine is still less active and less irritant, is decidedly anodyne and hypnotic, and very depressant to the respiration.
Therapeutics. Hyoscyamus is principally used as a hypnotic and anodyne when Opium is contraindicated. In—
- Acute Mania with high motor excitement, obstinate insomnia and varied hallucinations,—it is by far the best agent to use.
- Chronic Mania,—has been benefited by it more than by any other drug.
- Insanity marked by frequent delusions,—it is very efficient.
- Delirium Tremens, and the delirium of fevers,—it is an excellent hypnotic, but needs to be used in larger doses than are generally employed.
- Monomania of hypochondriacs,—is alleviated and often cured by it.
- Neuralgias,—have been much benefited by Hyoscine hypodermically.
- Nervous Coughs, Whooping Cough, especially a dry, tickling night cough,—are greatly alleviated by Hyoscyamus.
- Locomotor Ataxia,—Hyoscyamine for the pains and incoördination.
- Paralysis Agitans, mercurial tremor, etc.,—Hyoscine palliates the trembling.
- Colic of various forms,—Hyoscyamus has long been used.
- Constipation,—Purgatives are rendered more efficient and less drastic by combination with the Extract of Hyoscyamus.
A Compend of Materia Medica, Therapeutics, and Prescription Writing, 1902, by Sam'l O. L. Potter, M.D., M.R.C.P.L.