Increased aggression in rats after withdrawal of long term used oxazepam

Reduction of aggression during benzodiazepine withdrawal: effects of flumazenil

Benzodiazepine withdrawal has been associated with hostile and aggressive behavior. The benzodiazepine antagonist flumazenil has reduced, increased or not affected hostility and aggression in animal and human studies. In the present study we analyzed data collected in a placebo-controlled study of the effects of the benzodiazepine antagonist flumazenil in patients previously treated for benzodiazepine dependency, and healthy controls. The aim was to analyze the effects of flumazenil on hostility and aggression. Ten patients and 10 controls received, on two separate occasions, cumulative doses of flumazenil (0.05, 0.1, 0.25, 0.5 and 1mg at 15min intervals) or placebo. Withdrawal symptoms were rated after each injection. Patients had been free from benzodiazepines for 47 (4-266) weeks on the first occasion. A three-way interaction (groupxtreatmentxdose) was found, and was explained by: 1) patients rating aggression and hostility higher than controls at all times during placebo, while 2) during the flumazenil provocation i) the initial significant difference between patients and controls was no longer significant above the 0.5mg dose, and ii) patients rated aggression and hostility significantly lower above the 0.5mg dose compared to base-line. The results suggest that self-rated aggression and hostility in patients treated for benzodiazepine dependency was reduced by the partial benzodiazepine agonist flumazenil.

Aggressive and social behavior after alprazolam withdrawal: experimental therapy with Ro 19-8022

The aim of the present study was to ascertain whether withdrawal from alprazolam can increase anxiety-like and aggressive behavior during intra species conflict in mice and, if so, whether a partial benzodiazepine agonist Ro 19-8022 is able to reverse these behavioral changes without untoward effects such as sedation. An experimental model consisting of interactions of pairs of singly-housed male mice with non-aggressive group-housed male mice was used. Alprazolam (1 mg/kg) was given orally twice daily for 8 days and once on the 9th day. When withdrawn from alprazolam (3 days after the last dose), mice reduced social investigation and increased the incidence of aggressive behavior in comparison to the pre-withdrawal level. However, the increase of aggression was moderate and occurred only in subjects with low pre-treatment levels of aggression. Ro 19-8022 (10 mg/kg) significantly antagonized the decrease of social behavior and the increase of aggression after alprazolam withdrawal without causing sedation or ataxia.

Time course for development of benzodiazepine tolerance and physical dependence

Chronic benzodiazepine treatment elicits adaptive responses in the CNS, seen behaviorally as functional tolerance and physical dependence. Experiments are described in which a radioreceptor assay is used to follow benzodiazepine activity in CSF samples during daily flurazepam treatment of cats. Tolerance is evident even after the second dose, despite increasing CSF drug activity, showing a large and rapidly developing functional tolerance. Other studies are discussed which also show tolerance within 24 hours of initiating benzodiazepine treatment. In contrast, a spontaneous withdrawal syndrome is usually seen only after prolonged treatment with high doses. However, physical dependence can also be studied by precipitating abstinence with a benzodiazepine antagonist, such as Ro15-1788. Cats were treated daily with flurazepam, then Ro15-1788 was given and abstinence signs were recorded. Abstinence could be precipitated 24 hours after beginning treatment, and dependence was nearly maximal after 7 days. Dependence developed during treatment with as little as 0.5 mg/kg flurazepam, which is near threshold for any behavioral response. Chronic diazepam caused the same dependence as flurazepam. Thus, the development of tolerance and physical dependence both show a remarkably rapid adaptation of the CNS in response to benzodiazepines.