Thirty-one children (5 months to 19 years) with medically intractable childhood epilepsy had nitrazepam added to their antiepileptic drug (AED) regimen. All patients had previously received phenobarbital, phenytoin, carbamazepine, valproate, and at least one benzodiazepine. Most patients (22) had multiple seizure types, including atonic, tonic, myoclonic, complex partial, and generalized tonic—clonic, whereas nine had ony one seizure type. Initially, 24 patients (77.4%) had a greater than 25% decrease in seizure frequency, whereas 19 (61%) had an improvement of greater than 50%. Tolerance occurred in 12 of 23 (43.4%) responders, at a mean period of 7 weeks. Eight of these 12 improved after further nitrazepam dosage increases, maintaining a greater than 25% decrease in seizure frequency as compared to baseline. On follow-up (mean, 5.4 months), 65% of our 31 patients maintained a seizure reduction greater than 25%, and in 54% this reduction was greater than 50% ( p ⩽ 0.001, McNemar's test). We conclude that nitrazepam is a useful adjunctive AED in intractable childhood epilepsy despite the occurrence of tolerance in over one-third of the patients. Furthermore, previous failure of benzodiazepine therapy does not preclude a positive response to nitrazepam.