This section is from the "A Practical Treatise On Materia Medica And Therapeutics" book, by Roberts Bartholow. Also available from Amazon: A Practical Treatise On Materia Medica And Therapeutics
Vapors of medicinal substances, and gases, are conducted with the air into the bronchial tubes and the air-sacs. Vapor of creosote, carbolic acid, iodine, ethyl iodide, iodoform, bromine, etc., are thus employed with excellent effect. Those that require heat to be vaporized can be put in a warm vial or bottle, and the vapor then conducted to the nose or mouth by a cone of stiff paper, the base of the cone being large enough to cover the vessel in which the vapor is forming. Of the compounds of iodine, the most convenient and effective for inhalation is ethyl iodide. It requires no special contrivance, and does not have an anaesthetic effect that will narcotize. The warmth of the hand is sufficient to vaporize it, and hence it may be inspired from the vessel containing it. A few drops (ten to thirty) may be put on a folded napkin or handkerchief and inhaled, or the same quantity can be dropped in a vial previously warmed, and immediately inhaled. Ethyl-iodide vapor can be readily mixed with a proper proportion of nitrous oxide, or combined with the vapor of iodine, iodoform, creosote, carbolic acid, and with other antiseptics. Whatever difficulties are encountered are merely mechanical. In a recent issue of the "AEsclepiad" (1886), Dr. B. W. Richardson, of London, calls attention to the remarkable powers of ozonic ether as a remedy in pulmonary diseases—a recommendation which he holds is the most valuable he has ever contributed to practical medicine. His mode of procedure is described in the article referred to, and an abstract may be found in the "New York Medical Journal" of March 13, 1887.
Pyridin vapor has been brought out by Professor Sée, as an inhalant of remarkable efficacy in asthma and other neuroses of the respiratory apparatus. The air of an apartment of suitable size can be made by diffusion to contain a proper amount of pyridin vapor. As persons vary in susceptibility to the action of such a vapor, the necessary quantity must be ascertained by trial. Various permanent gases are now used by inhalation, in diseases of the respiratory mucous tract. An improvement warmly received, yet already waning, is the rectal injection of sulph-hydric and carbonic-acid gases. Bernard having shown, experimentally, that these gases when introduced into the rectum, escaped by the lungs without penetrating to the nervous centres, Bergeon, of Lyons, utilized this fact, and in this way proposed to act on the bacilli of tuberculosis of the lungs. The method was received with extraordinary favor, and in a few weeks was employed in all parts of the world. It was presently ascertained, however, that the bacilli were not destroyed, and the benefits derived did not compensate for the disagreeable incidents of the injections.
The suggestion of Dupont that the inhalation of the carbonic-acid gas should take the place of the rectal injection of the gases, and the growing belief in the superiority of inhalations, have quite occupied the field, and hence the rectal injections are no longer practiced. Prolonged inhalation of volatile materials is a mode rapidly growing in favor, and is supplanting douches, insufflation, and other kinds of topical applications. As air is a natural vehicle for access to the lungs, and as gases and volatile substances can pass into the air-sacs by means of it, the method of introducing medicaments by respiration is naturally superior to the various mechanical contrivances. Volatile medicines capable of diffusion through the air, and gases, may be thus used with success. The most powerful of these preparations is the liquid of the French chemist, Pictet. The sulphurous and carbonic-acid gases are liquefied by pressure and stored up in siphon bottles, from which they are readily obtained by a mere touch on the valve. It is obvious that such an arrangement is highly convenient, but the power for mischief must not be overlooked in estimating the curative value.