[Ulcerative stomatitis as clinical clue to inadvertent methotrexate overdose].

Gastrointestinal side effects and the development of toxic liver fibrosis are well-known side effects of low dose methotrexate therapy. A female patient receiving a long term low dose methotrexate therapy for a seronegative chronic polyarthritis developed an ulcerative stomatitis, as clinical clue to an inadvertently given methotrexate overdose. A summary of other side effects of methotrexate and of oral side effects of other cytostatic agents and immunosuppressive drugs is given.