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.
Much power has been claimed for peroxide of hydrogen in the relief of paroxysms of whooping-cough, but I have no experience of it. In a severe case, complicated with cyanosis, in a child with patent foramen ovale, Dr. Mackey used the remedy with apparently good result for the time; the degree of cyanosis was less while the remedy was taken, and the attack of pertussis ran a mild course.
Dr. Gibb was one of the first to ascertain the value of bromides in this disorder, and he found the ammonium salt to act best; it quickly relieved the whoop, i.e., the laryngeal spasm. Dr. G. Harley also early recorded satisfactory cases (Lancet, i. and ii., 1863). I have often verified this use of the bromides, especially in early stages. I order for children 3 to 5 gr. every two to four hours, as a rule not giving more than 20 gr. in the day, because of the depression induced in weakly subjects; I often combine belladonna, and sometimes chloral, with the treatment. Dr. Ringer reports them as useful only in simple, uncomplicated cases, but neither dentition nor a pyrexial state need prevent their use if the spasm continue; they are fairly presumed to lessen congestion in the medulla as well as in the mucous membrane of the fauces, and to diminish reflex excitability.
If catarrh be present, an expectorant may be conjoined, and if bronchitis or pneumonia supervene, the spasm generally subsides for a time, and a different treatment is indicated. The convulsion of pertussis I have frequently seen relieved by bromide, but belladonna is much more serviceable.
Nitric acid has been found by some observers valuable in relieving the spasmodic recurrent attacks of cough, and lessening profuse expectoration; and it may certainly be credited with tonic bracing action on the faucial and laryngeal membranes. Arnoldi, who introduced this mode of treatment, ordered as much acid as would render a tumblerful of sugared water "like lemon juice," to be taken every three or four hours. Dr. Gibb, who reported the best results, gave as much as 10 min. to infants, and 40 min. to children of ten years; and some other practitioners have used this medicine with success, as Ussher (Medical Times, i., 1862), and Berry - in an epidemic at Lancaster - who found it effective, safe, and cheap (Medical Times, i., 1873). I have been reluctant to press it for fear of injuring teeth, and when I have used it as freely as could be borne, I have not seen definite benefit.
I have seen relief given to the cough in later stages by inhalation of ammonia vapor, and Mr. Grantham has devised a simple method of effecting this by adding 1 oz. of the liquor to 1 gallon of boiling water in a bucket or bath, and then putting in a red-hot brick (British Medical Journal, ii., 1871). The atmosphere of gas-works has often relieved chronic cases, a good effect which has been traced to the volatile sulphide of ammonium.
The carbonate of potash was at one time in good repute in the treatment of whooping-cough, but we cannot expect more from it than the thinning of tracheal and bronchial secretion, and a slight sedative effect on the mucous membrane. The acetate has been especially recommended (Practitioner, vol. ii.), also the sulphuret; the latter is given in doses of 1 gr. per year up to four years, after that age in the proportion of 1/2 gr. per year. It is important that its solution should be freshly prepared: it is rather nauseous, and acts sometimes as an emetic, but if continued for four or five days will usually do good (Ranking, i., 1869, p. 65).