Advantages of histamine H4 receptor antagonist usage with H1 receptor antagonist for the treatment of murine allergic contact dermatitis.

Histamine facilitates development of eczematous lesions in chronic allergic contact dermatitis. In addition to the well-known corticosteroid treatments, H1 receptor (H1R) antagonists also have been used. This study observed effects of histamine H4 receptor (H4R) antagonist usage with H1R antagonist in a murine chronic allergic contact dermatitis model, developed by repeated percutaneous challenge to the dorsal skin with 2,4,6-trinitro-1-chlorobenzene (TNCB). The H1R antagonist olopatadine hydrochloride and/or the H4R antagonist JNJ7777120 was then administered. Combination therapy was more effective than H1R antagonist monotherapy. Serum IgE and levels of interleukin (IL)-4, IL-5 and IL-6 (Th2 cytokines) in eczematous lesions decreased with combined therapy. Combined therapy with H1R and H4R antagonists counteracts the disadvantages of each as monotherapeutic agents and potentially represents a new strategy for the treatment of chronic allergic contact dermatitis.