This section is from the book "Materia Medica And Therapeutics Inorganic Substances", by Charles D. F. Phillips. Also available from Amazon: Materia medica and therapeutics.
Dilute alkaline solutions taken into the stomach before meals augment the secretion of gastric juice (Blondlot, C. Bernard), for if digestion is to continue, fresh secretion must occur to compensate for what is neutralized; also the chlorides that are formed augment the secretion (Rabuteau). "They favor the outward osmosis of those constituents of the blood from which the acid of the stomach is elaborated" (Bartholow). But alkalies given in too large or too concentrated a dose arrest the secretion, and if given soon after a meal prevent even a normal amount of acidity. Dr. Ringer formulates a general proposition thus: - "Alkalies applied to the orifices of glands with acid secretions increase their secreting power, while alkalies applied in a corresponding way to glands with alkaline secretion lessen or check this secretion;" and I think that, as a general rule, and with due regard to the strength of solution, this may be held true.
The increased secretion of saliva caused by direct application of alkalies is thick, whitish, and cloudy; it is not large in amount, and there is some doubt as to whether it is true secretion or (as Kuhne thinks) the result of a rapid degeneration of the gland. A similar fluid results from irritation of the sympathetic nerves of the submaxillary gland, and hence the alkali has been thought to act through the sympathetic. The chlorate of potash sometimes acts so as to produce a degree of salivation.
Under the influence of alkalies taken internally, the bile and pancreatic juice are increased in amount, and rendered more fluid. The sulphate of potash given internally has special power in this direction (Rutherford), more than magnesia. The bronchial secretions are also increased and fluidified by alkalies, and the movements of ciliated epithelium are rendered more active by them.
Secretion from the intestinal glands is augmented, especially by full doses of the potash salts of mineral acids: 2 or 3 dr., e.g., of the sulphate cause watery purging; larger quantities sometimes irritate much: 1/2-oz. doses have been used in France as abortifacient with serious effects (Mowbray), and 2 oz. have caused death (Taylor).
The nitrate in small doses is absorbed and produces some constipation, but in full doses and well diluted causes diarrhoea (Martin Solon, 1843). Orfila reported violent irritation of the mucous membrane from its use, and an ounce has caused death with irritant symptoms and depression, though this is exceptional. The experiments of Rognetta indicated only a moderate degree of congestion - no inflammation; and ounce doses, when well diluted, have been given medicinally without serious result.
The chlorate may also irritate mucous membranes, and in large doses has sometimes, though rarely, caused death through this effect, e.g., in a patient with phthisis, who took 300 gr. daily for four days, and in the case of Dr. Fountain, who unfortunately took an ounce in order to prove his conviction of its innocent character (Stille).
The bichromate in small doses increases all the secretions, in large doses acts as an irritant poison, and induces suppression of urine.
The urine is often markedly increased in quantity by liquor potassae (Parkes), by the bicarbonate and the chlorate, but still more by the bitar-trate, nitrate, acetate, and citrate; the increase is not always decided, unless the urine is rendered alkaline. There is a marked difference in different compounds as to their production of alkalinity: thus, a single dose of 40 gr. of acetate alkalinized the urine in a few hours, and then was not all changed, but of the bicarbonate several drachm doses were required. In febrile diseases, salines, such as nitrate of potash, may cause at first marked lessening of excretion, afterward increase (Parkes: Medical Times, i., 1855). In cases of irritant poisoning by the potash salts of the mineral acids, suppression of urine has occurred, probably reflex in character.
The other alkalies are allied in chemical action to the salts of potash, and acids are the chemical antagonists. Gubler suggests that soda is antagonistic to potash (dynamically) in its action on the blood and on respiratory combustion, because potash only, not soda, is contained normally in corpuscles, and under certain conditions may be replaced by the latter when given in full doses.
Caustic potash has been used in surgery for the same purpose as other powerful caustics, and has the special characteristics of being deliquescent and of dissolving and deeply penetrating the tissues; parts near the seat of its application should therefore be protected by plaster, or by oil, and the cauterized place should be sponged with dilute vinegar to prevent undue action. The slough caused by it is leathery, soft, dark-colored, and moist, not dry like that of nitrate of silver: it separates after a variable time, according to its thickness.