weeks. The serum level of elastase remained unchanged. The administration of lactoferrin in the chronic phase of adjuvant arthritis resulted in a steady suppression of the inflammatory process (decreased hind paws swelling and local temperature, white blood cell count and erythrocyte sedimentation rate, an increase in weight gaining and a decrease in serum elastase level), which lasted until the end of experiment (day 50). This effect was achieved with lower doses of the drug (9 mg/kg), though its strength was dose-dependent. The maximal suppression of adjuvant arthritis was obtained with the repeated injections of lactoferrin (5 injections every other day with total dose of 60 mg/kg) in the chronic phase of adjuvant arthritis (days 23-31). In these rats the serum concentration of elastase was reduced down to normal level and the rate of generalisation was less than 8%. Conclusion Lactoferrin is a potent anti-inflammatory agent effective in treatment of adjuvant arthritis in rats. The maximal suppression of the inflammatory process is obtained in the chronic phase of adjuvant arthritis.