Disclosed is a novel means which enables treatment or prophylaxis of pruritic dermatoses such as atopic dermatitis. As a result of intensive study, the present inventors discovered that an antimicrobial peptide LL-37 has an action to promote expression of a nerve repulsion factor Sema3A. LL-37 is a peptide composed of the C-terminal 37 residues of human cathelicidin hCAP18. Use of this antimicrobial peptide enables normalization of expression of axon guidance molecules such as nerve repulsion factor in lesions of pruritic dermatoses including atopic dermatitis and xeroderma, and thus enables alleviation of pruritus and amelioration of skin lesions.
