Abstract: Subcutaneous injection of lycorine at a dosage of 12 mg/kg once daily for 3 consecu- tive days induced marked involution of thymus in immature mice. Intravenous injection of a dose of 12 mg/kg of lycorine significantly depleted the adrenal ascorbic acid con- tent of the rabbit. Lycorine, at a dosage of 16 mg/kg, elicited eosinopenic response in the intact toad, but failed to induce similar response in the hypophysectomized animal. These results indicate that lycorine affected the function of the adrenal cortex presum- ably through stimulation of ACTH release. In addition, lycorine was found to possess anti-inflammatory activity on egg-white- induced oedema of the hind paw in intact rats, and on formalin-arthritis in rabbits (3mg/kg I.V.). However, lycorine failed to inhibit egg-white-induced oedema in ad- renalectomized rats. Thus, the anti-inflammatory action of lycorine is probably mediated by stimulating the pituitary-adrenal system.