Naloxone fails to prolong seizure length in ECT

Electroconvulsive shock (ECS) in animals has been shown to enhance endogeno us opiate systems. The anticonvulsant effects of ECS are also partially blo cked by the opiate receptor antagonist naloxone, leading some investigators to postulate that the anticonvulsant effects of ECS are mediated by activa tion of endogenous opiates. Lf such a phenomenon occurs in humans, then nal oxone might prolong seizure length in electroconvulsive therapy (ECT). In t he present study, nine patients were given 2.0 mg intravenous (i.v.) naloxo ne 2 minutes prior to one-half of their ECT treatments. Motor seizure lengt h was measured via the cuff technique. EEG tracings were wad by an investig ator blind to naloxone status. There was no difference between the two grou ps in either EEG or nonblindly evaluated motor seizure length. It is conclu ded that a dose of 2 mg naloxone does not effectively increase seizure leng th in ECT.