The psoriatic lesions of seven male patients were treated with a daily topical application of 10 mg of mechlorethamine hydrochloride in 50 ml of tap water. All seven patients began to show resolution of the treated lesions within seven days, with essentially complete clearing of the lesions by three weeks. Untreated lesions remained unaffected, and no alteration of hematopoietic or hepatic function was seen. One patient developed allergic contact dermatitis.
Mandy S, Taylor JR, Halprin K. Topically Applied Mechlorethamine in the Treatment of Psoriasis. Arch Dermatol. 1971;103(3):272-276. doi:10.1001/archderm.1971.04000150042006