The sedative effect of medetomidine was evaluated in 6 male Awassi sheep. Medetomidine at 40 micrograms/kg, i.m. induced sedation and recumbency in the sheep within 9 +/- 1 and 17 +/- 4 minutes, respectively. The duration of recumbency was 58 +/- 1 minutes. Medetomidine produced good analgesia and marked muscle relaxation in the recumbent animals for 30 to 45 minutes. The side effects of medetomidine were bradycardia, respiratory depression, stasis of the rumen with tympany, salivation and polyuria. The animals recovered from the sedative and side effects of medetomidine 1.5 to 2 hours after gaining the righting reflex without any apparent adverse effect. The results suggested that medetomidine could be a useful sedative analgesic in sheep.