21 CFR § 358.510
Corn and callus remover active ingredients
June 25, 2020
The product consists of any of the following active ingredients within the specified concentrations and in the dosage form established for each ingredient.
(a) Salicylic acid 12 to 40 percent in a plaster vehicle.
(b) Salicylic acid 12 to 17.6 percent in a collodion-like vehicle.