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 true goitre, as distinguished from fibroid or purely cystic enlargements, an ointment of the red iodide of mercury succeeds, according to the large Indian experience of my colleague, Mr. Macnamara, better than any other remedy.1 The strength he recommends is of 15 gr. to the ounce of cerate, more than this causing unnecessary pain and soreness. A thin coating of such an ointment should be smeared over the goitre, which should then be exposed to the full rays of the sun, or at least to bright light: artificial heat is not so effective (Frodsham: Lancet, i., 1860). Within half an hour smarting and burning are felt, and in another hour a blister forms, which needs to be treated only in the usual way. The good effects of the red iodide continue long after this blister has healed, the tumor decreasing day by day for several weeks. One application of the ointment every two months is sufficient for the most extreme cases. Mr. Macnamara has often seen tumors which extended from the chin to the breasts disappear after two or three applications; from ordinary blisters he has never seen benefit in such cases, and the expensive iodine ointment was found to act very slowly, compared to the mercurial preparation: he has never seen salivation produced by the red iodide, though it is said to have occurred in some exceptional cases.
1 The credit of this application has been variously ascribed to Major Holmes, Captain Cunningham, or Grant. Mr. Macnamara's experience is based on 23,000 cases.