RESUMO
Most patients with atopic dermatitis (AD) have a good response to topical treatment. However, some need systemic therapy in order to satisfactorily control the disease. Azathioprine is an accessible drug for patients in many countries, including underdeveloped countries, and therefore it is used by many dermatologists in moderate and severe AD. It is important to have a deep knowledge and understanding about this drug since it is an alternative therapy as a steroid-sparing agent and an affordable one. However, when it comes to systemic therapy for AD, it is not always clear its indications and it is necessary to have a closer follow-up of the patient. In this paper, we describe thoroughly its indications in AD, the mechanism of action of the drug, as well as the interactions, adverse effects, adequate monitoring, and precautions in special population that must be considered when prescribing azathioprine. This review will help dermatologists prescribe it safely to all patients who require it.