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 these conditions generally, phosphoric acid fulfils many indications as a grateful moderately astringent tonic; it relieves hoarseness and dry irritating cough accompanied by pain and laryngeal soreness. Dr. Cotton gave it to twenty-five patients with chronic uncomplicated phthisis at Brompton Hospital, and observed benefit in a few advanced cases: it improved appetite and controlled secretion, although sometimes nausea and pain were excited: he could not trace a specific effect from it, but rather the action of a general nerve-tonic; it acted specially well combined with iron (Medical Times, i., 1863). Dr. C. J. B. Williams recommends it with cod-liver oil (Lancet, ii., 1868, p. 213).
In the dyspepsia so common in phthisis, it is also useful, relieving the pain, sickness, and diarrhoea which occur after meals. Profuse night-sweats and other exhausting discharges are controlled by it, and it exerts a sedative effect upon the excessive sexual desire which often developes in some stages of phthisis. Dr. Todd used it in cardialgia.