The decision for treating patients with chronic systemic sarcoidosis is often difficult and controversial. Methotrexate (MTX) has been used to treat patients with chronic forms of the disease for years, although prospective, randomized studies assessing the efficacy and toxicity of this agent are lacking. This is the follow-up study of 91 patients with the chronic form of pulmonary and extrapulmonary sarcoidosis who were treated with MTX. All patients experienced treatment with corticosteroids before they were administered MTX. Most of the patients treated with MTX showed improvement on chest radiographs, lung function tests, and extrapulmonary signs of the disease 6 months after the treatment began. No side effects that would cause the patients to discontinue the treatment were observed.