Shingles: More than Meets the Eye.

Low-dose once weekly methotrexate (MTX) is the first-line disease-modifying antirheumatic drug (DMARD) to treat rheumatoid arthritis and psoriasis. Although methotrexate is generally considered to have a good safety profile it can occasionally induce severe side effects such as pancytopenia, mucositis, disorders of kidney and liver. Oral mucositis should alert physicians to MTX toxicity.