Provided is a pharmaceutical composition for external use, including: (i) a compound represented by the general structural formula (1) and/or a salt thereof; and (ii) N-methyl-2-pyrolidone :Where, X represents a hydrogen atom or a chlorine atom.提供一種外用醫藥組成物,包含:i)以結構式(1)所代表之化合物及/或其鹽類;及ii)N-甲基-2-吡咯啶酮:其中X代表氫原子或氯原子。