[Methotrexate toxicity. Myths and facts].

Methotrexate (MTX) is a safe and well-tolerated drug for the treatment of rheumatic diseases, even if the strictest safety standards are considered. Initial apprehension as to severe pulmonary or hepatic side-effects has not been confirmed. The risk of infection is not elevated compared with other disease-modifying antirheumatic drugs. In addition, a mutagenic potential could not be demonstrated even after long-term application. Therefore, MTX will maintain its significant role in antirheumatic therapy also in the near future.