Analgesic effect of amygdalin (AM) in mice was observed in hot plate and acetic acid-induced writhing tests. AM did not induce tolerance as morphine did, and did not cause morphine-characteristic tail-erecting response in mice. Mice given AM and then challenged with nalorphine showed no jumping response. AM could not substitute for morphine in morphine-addicted rats in relieving withdrawal syndrome. No antiinflammatory activity was found with AM.