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.
To treat this inflammation without mercury would, a generation ago, have been reckoned almost criminal, and men no less eminent than Graves and Stokes have left their emphatic testimony in its favor - the latter gave 20 gr. of calomel once or twice daily. Yet soon afterward, Markham and Walshe began to doubt its value, and Todd denied it wholly. Watson says, "I am obliged to recant my advice as to giving mercury in acute pericarditis" ("Lectures," 1871), and Hayden is almost alone among modern writers in still recommending calomel and antimony ("Diseases of Heart," 187G). Waters, Austin Flint, and Loomis have discarded mercurials, and Sibson, in his able monograph, does not even mention them ("Reynolds' System," vol. iv.). Dr. Garrod states that full mercurial treatment of the joint-affection in rheumatism will not prevent pericarditis, and it would seem, therefore, scarcely likely to arrest it after its commencement: further, as it is almost always connected with, or dependent upon, rheumatism, its treatment should naturally be conducted on the same principles, and as we do not now give mercury for the main disease, why should we do so for one of its local manifestations? I have myself carefully watched its effects several times, and although the bruit and other physical signs have varied during the attack, I have never been able to satisfy myself of a definite influence of the drug upon the malady; on the contrary, I have seen this prolonged to more than an ordinary duration, while the gums have been sore. In subacute or chronic cases, where effusion has occurred and is persistent, I have seen benefit from small doses of sublimate or gray powder and mercurial applications locally, but when the effusion is very large, the pulse feeble, and cardiac paralysis threatening, any excess of mercury must be carefully avoided (Nothnagel).