In the present study, the neuromuscular function following the administ ration of atracurium, gallamine, or pancuronium was evaluated using the upper lip muscles preparation of anaesthetised dogs. Moreover, the interactions of these drugs with chlorpromazine were investigated. The onset time, duration of action and recovery index of these muscle relaxants were measured.
The prior administration of chlorpromazine potentiated and prolonged the inhibitory effect of atracurium, gallamine or pancuronium with marked reduction of their doses. The importance of these findings in anaesthetic practice was refered to.