The dose of the Tincture of Physostigma (Tinctura Physostigmatis) is from 5 to 20 minims (0.3-1.2 c.c.); of the Extract of Physostigmatis (Extractum Physostigmatis), ¹/₁₂ to ⅙ of a grain (0.005-0.01 gm.); of eserin or physostigmin and its salts, ¹/₁₅₀ to ¹/₅₀ of a grain (0.0004-0.0013 gm.).
Pilocarpus, or Jaborandi.—This is the leaves of a South American plant. Its virtues depend entirely upon an alkaloid known as pilocarpin. The chief action of the drug is on the secretions—sweat, saliva, and urine—which it markedly increases. Large doses depress the circulation. Locally, in the eye, it contracts the pupil like eserin. It is mainly employed internally as a diaphoretic in Bright’s disease and dropsical conditions. The dose of the Fluid Extract (Extractum Pilocarpi Fluidum) is from 20 to 60 minims (1.5-4 c.c.); of pilocarpin and its salts, ⅛ to ½ grain (0.008-0.03 gm.). The latter are usually administered hypodermically.
Quinin.—See Cinchona.
Salicylates.—These salts are employed in medicine chiefly as antirheumatic remedies. Their manner of action, however, is unknown. They are also used, both internally and externally, to some extent as antiseptics. Large doses cause ringing in the ears, headache, deafness, nausea, and a greenish discoloration of the urine.
The dose of salicylic acid or its salts (ammonium, sodium, strontium) is from 5 to 20 grains (0.3-1.3 gm.); of Oil of Gaultheria (Methyl Salicylate), 5 to 20 minims (0.3-1.2 c.c.). These preparations should be given after meals, well diluted.
The following remedies have properties like the salicylates, but are less powerful and less irritant to the stomach: Salol, dose, 5 to 20 grains (0.3-1.3 gm.); salophen, 5 to 30 grains (0.3-2 gm.); aspirin, 5 to 20 grains (0.3-1.3 gm.).
Senna.—This is a purgative cholagogue and is used in the constipation of children and pregnant women. Dose, in substance, 5 to 20 grains; in fluidextract or tincture, 1 to 4 fluidrams.
Silver.—The most important salt of this metal is the nitrate. Locally, in concentrated form, the latter is a caustic; in dilute form it is a sedative, astringent, and antiseptic. Internally, in small doses, silver nitrate is useful as an astringent and antiseptic in inflammatory and ulcerative conditions of the stomach and bowel.
The prolonged use of the drug, even in small doses, is followed by a permanent grayish discoloration of the skin (argyria) from the precipitation of the metal in the tissues.
Toxic doses of silver nitrate cause burning pain in the abdomen, vomiting of white, curdy matter, and bloody purging.