Mercury Nitrate: solution topically.
Mercury Bichloride: solution as wash.
Mercury Iodide, red.
Naphtol.
Nitric Acid.
Perosmic Acid.
Phosphorus: in chronic cases in place of arsenic. The phosphates and hypo-phosphites are safer and more valuable. The latter in acne indurata.
Potassium Bromide: sometimes useful in moderate doses in obstinate cases. This salt and the Iodide very often cause acne when taken continuously.
Potassium Chlorate.
Quinine.