allium sativum l is widely used by cuban people in folk and natural medicine to alliviate inflammatory processes and specially in rheumatoid arthritis; however, its activity hasn’t scientifically enough demonstrated to stablish a clinical assay for its registration and industrial production. in present paper, action of a allium sativum syrup on experimental rheumatoid arthritis was assessed, using models of leg edema and pleurisy in wistar rats, based on passive reaction of arthus. in two models, placebo and doses of 45, 90, and 180 mg/kg of body weight were assayed based on total solids in a.sativum syrup. as positive controls ibuprofen and prednisone were used at dosis of 200 and 10 mg/kg, respectively. positive controls and assayed dosis of allium sativum l syrup decreased inflammatory process triggered by antigen-antibody reaction achieved by means of passive reaction of arthus, by means of egg albumin antiserum, and bovine albumin antiserum for leg edema and development of pleurisy, recpectively.