The benzodiazepine sensitivity test, an intravenous bolus of diazepam (0.2 mg/kg) under EEG control, was used in 40 children with intractable seizure disorders treated in the Paediatric Neurology Service and the Dept Neurology and Clinical Neurophysiology, Royal Hospital for Sick Children, Edinburgh. The etiology and clinical patterns of seizures were heterogeneous, 50% symptomatic of various causes and 63% with a mixed seizure disorder, atypical absences, myoclonic and drop or atonic seizures predominating. EEG abnormalities were severe and persistent. Many different drugs had been used but 29 (73%) patients had not received benzodiazepines.
A positive effect, defined as abolition of abnormal EEG activity often with appearance of fast activity, was obtained in 53% of the total group. The response was negative in 6 of 7 patients in non-convulsive status and in 7 of 9 patients with Lennox Gastaut syndrome, 2 showing exacerbations of EEG paroxysms and clinical seizures. All 5 with focal spikes responded whereas only 3 of 6 with hypsarrhythmia showed improvement in the EEG.
Of 32 patients treated subsequently with long-term oral benzodiazepines, 21 (66%) showed improvement in seizure control. Among those benefitted, the diazepam sensitivity test had been positive in 76%. Of 11 patients unresponsive to oral benzodiazepines, only 36% had shown a positive sensitivity test. The authors conclude that the test is of value in long-term management of intractable childhood seizures but emphasize the variability and unpredictability of the response to oral benzodiazepines. 
COMMENT. This practical study confirms the value of the EEG and intraveneous drug sensitivity in the management of childhood epilepsy but with some limitations. It contradicts the recommended choice of benzodiazepines in the treatment of non-convulsive status [2, 3]. Development of tolerance is the greatest limitation to the long-term use of benzodiazepines in myoclonic and other epilepsies, occurring in 80% of 36 children treated with nitrazepam at Children’s Memorial Hosp, Chicago.