Neuropsychological function can be permanently affected by abuse of certain hypnotic benzodiazepines (temazepam, nitrazepam, flunitrazepam, and nimetazepam were found to be particularly toxic), with brain damage similar to alcoholic brain damage, as was shown in a 4– to 6-year follow-up study of hypnotic abusers by Borg and others of the Karolinska Institute. The CT scan abnormalities showed dilatation of the ventricular system. However, unlike alcoholics, hypnotic abusers showed no evidence of widened cortical sulci. The study concluded that, when cerebral disorder is diagnosed in hypnotic benzodiazepine abusers, it is often permanent. An earlier study by Borg et al. found evidence of cerebral disorder in those that exclusively abused hypnotic benzodiazepines, suggesting that cerebral disorder was not the result of other substances of abuse. Anxiolytic benzodiazepines, such as diazepam, clonazepam, alprazolam, bromazepam and lorazepam were not found to have the same toxic properties of most of the hypnotics.
