A composition for use in a method of treatment. The composition for use in treating a skin disorder, comprising an alkylating agent which is mechlorethamine hydrochloride, wherein the alkylating agent is in a non-aqueous vehicle or carrier that does not include petrolatum or ethanol. The method comprises topically applying the composition of the alkylating agent to the affected skin, wherein the alkylating agent is in a non-aqueous vehicle or carrier that does not include petrolatum or ethanol.
