Chronic urticaria is a relatively common disorder that can be severe and may impair quality of life. The management of recalcitrant chronic urticaria that is not responding to histamine antagonists includes short-term systemic corticosteroids, anti-inflammatory drugs (colchicine, dapsone and sulfasalazine) and immunomodulatory agents, such as cyclosporine, methotrexate, plasmapheresis and intravenous immunoglobulin.

We report here our retrospective experience with the use of methotrexate in 8 patients (2 males and 6 females) with recalcitrant chronic urticaria who were not responding to high-dose first- and second-generation antihistamines. The mean duration of the disease prior to methotrexate treatment was 12 ± 8 months. Patients were treated for a mean duration of 4.5 months with a mean dose of 15 mg methotrexate/week.

A complete response was achieved in 7 out of 8 patients (87%). Five out of the 7 patients were disease-free during a period of 1-10 months follow-up after discontinuing methotrexate and prednisone therapy. No serious adverse effects were reported.
Methotrexate is an effective and safe treatment for chronic urticaria in patients who are not responsive to conventional therapy.

Ref: http://www.docguide.com/evidence-methotrexate-useful-treatment-steroid-dependent-chronic-urticaria?hash=80445d1a&eid=19508&alrhash=2efbb8-880279c42369cc2f8adcb48a6daaf3d2