This section is from the book "A Treatise On Therapeutics, And Pharmacology Or Materia Medica Vol1", by George B. Wood. Also available from Amazon: Part 1 and Part 2.
This is the Hyoscyamus niger of botanists, an annual or biennial herbaceous plant, indigenous in Europe, where it is also cultivated for medical use. It has been introduced into this country, and grows wild in some of our Northern States, especially in Michigan, where it abounds in the neighbourhood of Detroit, The whole plant is possessed of medicinal virtue. The U. S. Pharmacopoeia recognizes the leaves and seeds.
Hyoscyami Folium. U.S. - Hyoscyamus. Br.
The leaves of henbane, in their recent state, are somewhat hairy, viscid to the touch, of a sea-green colour, of a strong, disagreeable, narcotic odour when bruised, and of a mucilaginous, somewhat acrid taste. By drying they become nearly or quite inodorous and tasteless. They impart their virtues to alcohol and water. By destructive distillation, they yield a very poisonous empyreumatic oil.
Hyoscyami Semen. U. S.
The seeds are very small, roundish, compressed, of a grayish or yellowish-gray colour, in odour like that of the plant, and a bitter, oily taste. They are stronger than the leaves, but less used.
Active Principle. There is little or no doubt that the virtues of henbane reside in a peculiar alkaloid, denominated hyosciamia, which, however, though it has been isolated and accurately described, and its effects upon the system investigated, has scarcely been introduced into use as a medicine. It exists most largely in the seeds, but in small proportion even in these. Experiment has proved that both it and its salts are very poisonous. M. Gustavo Lemattre, who has carefully investigated the physiological action of this and other alkaloids of the solanaceae, with the view of determining their relations to one another, was unable to discover any appreciable difference, in this respect, between hyoscyamia and the two better known alkaloids, atropia and daturia. (Archives Generates, Aout, 1865, p. 186.) Dr. A. B. Garrod, of London, has satisfactorily determined that the caustic alkalies, potassa and soda, entirely destroy the activity of hyoscyamia, and render hyoscyamus inert, in reference both to its local and general effects. It is not, however, injuriously affected by the carbonates of the same alkalies. (Med. Times and Gaz., Dec. 1857, p. 589).