STUDIES ON THE EFFECT OF LOW-DOSE METHOTREXATE ON RAT ADJUVANT ARTHRITIS

Adjuvant arthritis in rats was induced by the intradermal administration of Freund's complete adjuvant. When these immunized rats were treated orally with low doses of methotrexate (150-600 micrograms/kg/week) a statistically significant suppression of paw inflammation was observed. This low dose of methotrexate was comparable to that used in the treatment of human rheumatoid arthritis (RA). Our results are the first demonstration of the efficacy of low dose methotrexate in an animal model of human RA.