This section is from the book "A Practitioner's Handbook Of Materia Medica And Therapeutics", by Thos. S. Blair. Also available from Amazon: A Practitioner's handbook of Materia Medica and Therapeutics.
Ichthyol. An antiphlogistic, antiseptic, and alterative. Internally, its action is akin to sulphur, but its indications are not very clear and it is seldom so used.
Some cases of nephritis respond to it. The homeopaths extol its lower "potencies" in chronic rheumatism and chronic hives and in stomach troubles with nausea and increased appetite.
Externally, it is used in from 5 to 50% proportions in ointments, lotions, etc., in erysipelas, lymphatic indurations, rheumatism, indolent injuries, scrofulous enlargements, and a host of skin diseases. Glycerine tampons to uterine os, 10%; bougies in gonorrhea, I or 2 I. Use pure in ivy poisoning; 10% in oil sweet almonds, as an application in variola; in rheumatism, 3ii to adeps Ki. Before applying ichthyol, wash the parts with warm water and dry. After application to joints or severe lesions, it is well to cover parts with flannel and guttapercha tissue.
There is no occasion to give over 30 I (or grains) per day in any case, and it is wise to begin in any case except in ivy poison with ointments not exceeding 25%.