Duofilm also known as Salicylic acid is a medication is commonly used to remove the outer layer of the skin . As such, it is used to treat warts , psoriasis , acne vulgaris , ringworm , dandruff , and ichthyosis .
Salicylic acid is used in the production of other pharmaceuticals, including 4-aminosalicylic acid , sandulpiride , and landetimide (via salethamide )