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.
M. Chrestien, of Montpellier, and later, M. Legrand, have reported many cases of both primary and secondary syphilis cured under the influence of gold, and Trousseau observes that such results are now well proven and incontestable. Chancres and condylomata have got well under this remedy in a manner not likely to be due to nature, and in my own experience its efficacy has been still better seen in the later developments, such as ulceration in the nose and larynx, cutaneous syphilides, hard nodes, etc. It is said to cure without local applications, but often an "unguentum auri" has been used in addition. Gold may especially be employed in long-standing cases with chronic periostitis, and when mercury has been already given to saturation.
Dietrich, while denying to gold any true anti-syphilitic power, thought it most valuable for mercurial cachexia (journal des connaissances med Chir., 1840), but this has not been corroborated by many observers. Auric fever may occur during a course of the remedy, and for a time the general health may suffer, and the local manifestations may be more irritable, but on lessening the dose, pyrexia subsides, and good effects are more conspicuous.