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.
In the form of a warm, finely atomized spray, solutions of lime (1 in 30) have been much commended as chemical solvents of croupous membrane. Forster, Biermer, and others have shown that such membranes, and especially their fibrinous constituents, are soluble in lime-water (Archiv der Heilkunde, v., p. 522), but doubts have been expressed whether such an effect can be usefully and practically obtained in the living body. Biermer treated a true case of membranous croup (verified by rejection of membrane) by means of a warm lime-spray, and although the patient was in great peril, he obtained relief and finally recovered; - this physician, however, generally gave calomel at the same time (British and Foreign Review, July, 1865). Kuchenmeister has recorded several good cases treated successfully by the spray (Bulletin Gen., April, 18G5), and the experience of Steiner proved that diphtheritic layers on the fauces were dissolved by it in a marked manner: subsequently, however, the growths formed again, and could not be controlled by the remedy (Jahrb. fur Kinderheilk., 1870). Beigel has reported good results with it in croup, and Geiger, of Philadelphia, in diphtheria (Practitioner, i., p. 101); but Senator has more recently written against its employment, even from a theoretical point of view, and doubts its power of dissolving membranes "in situ." Gottstein and others consider the direct application of lime-water to the larynx by means of a brush to be more advantageous than the spray, and Albers, of Berlin, in desperate cases has injected the solution into the larynx from below, passing his syringe between the tracheal rings: cough was caused, and shreds of membrane were ejected (Berlin. Klin. Woch., February 1, 1869; Ranking, i., 1870). The experience of the profession is not yet such as to enable us to decide the real value of lime-water applied locally in the treatment of these affections, but my own results have not been largely in its favor. Mackenzie finds it useful "when the false membrane is not very thick" ("On Diphtheria," p. 69).
Lactic acid and carbonate of lithia act similarly, and even better, in dissolving croupous membranes; Kuchenmeister, however, still maintains the superiority of lime-water. Sanne recommends the saccharate.