Alternative agents in refractory chronic urticaria: evidence and considerations on their selection and use.

Patients with chronic urticaria (CU) who are refractory to antihistamines are frequently encountered by allergy specialists. Several alternative agents have been used to treat these patients; however, the evidence to support these agents is generally limited. This review focuses on some of the more commonly used alternative agents in refractory CU, including anti-inflammatory agents (montelukast, hydroxychloroquine, dapsone, sulfasalazine, methotrexate, colchicine), immunosuppressants (cyclosporine, tacrolimus, mycophenolate), and immunomodulatory agents (omalizumab, immune globulin). The evidence to support their use, dosing, potential toxicity, monitoring, and selection of these alternative agents is reviewed. Although numerous knowledge gaps exist for alternative agents in refractory CU, a rational, patient-based approach can be used with a goal of improving control and quality of life and minimizing adverse medication effects.