Agonist substitution for high-dose benzodiazepine-dependent patients: let us not forget the importance of flumazenil

Slow subcutaneous infusion of flumazenil for the treatment of long-term, high-dose benzodiazepine users: a review of 214 cases

Despite the first reports concerning benzodiazepine dependence being published in the early 1960s literature, the risk of benzodiazepine addiction is still greatly debated. The severe discomfort and life threatening complications usually experienced by long-term benzodiazepine users who suddenly interrupt benzodiazepine intake have led to the development of several detoxification protocols. A successful strategy used by our Addiction Unit is abrupt benzodiazepine cessation by administering flumazenil slow subcutaneous infusion (FLU-SSI) with an elastomeric pump. Although some studies proved the efficacy of flumazenil infusion more than 20 years ago, only a few centres in the world offer this method to their patients. This paper reports the data related to 214 subjects addicted to high doses of benzodiazepine and treated with the FLU-SSI method between 2012 and 2014. This technique is less invasive and requires less nursing intervention than intravenous infusion. Our data support FLU-SSI as a possible efficient strategy for the treatment of patients with long-term, high-dose benzodiazepine addiction, and could become a routine therapy as long as the necessary further studies on dose, duration of infusion and safety issues are carried out.

Benzodiazepine dependence and its treatment with low dose flumazenil

Globally benzodiazepines remain one of the most prescribed medication groups, especially in the primary care setting. With such high levels of prescribing it is not surprising that benzodiazepine dependence is common, cutting across all socioeconomic levels. Despite recognition of the potential for the development of iatrogenic dependence and the lack of any effective treatment, benzodiazepines continue to be widely prescribed in general practice. Conventional dependence management, benzodiazepine tapering, is commonly a protracted process over several weeks or months. It is often associated with significant withdrawal symptoms and craving leading to patient drop out and return to use. Accordingly, there is a worldwide need to find effective pharmacotherapeutic interventions for benzodiazepine dependence. One drug of increasing interest is the GABAA benzodiazepine receptor antagonist/partial agonist, flumazenil. Multiple bolus intravenous infusions of low dose flumazenil used either with or without benzodiazepine tapering can reduce withdrawal sequelae, and/or longer term symptoms in the months following withdrawal. Preliminary data suggest that continuous intravenous or subcutaneous flumazenil infusion for 4 days significantly reduces acute benzodiazepine withdrawal sequelae. The subcutaneous infusion was shown to be tissue compatible so the development of a longer acting (i.e. several weeks) depot flumazenil formulation has been explored. This could be capable of managing both acute and longer term benzodiazepine withdrawal sequelae. Preliminary in vitro water bath and in vivo biocompatibility data in sheep show that such an implant is feasible and so is likely to be used in clinical trials in the near future.

Lormetazepam addiction: data analysis from an Italian medical unit for addiction

Background

The purpose of this study was to determine, in the context of a hospital addiction unit, which benzodiazepines were abused and to look for correlations with the characteristics of detoxified patients.

Methods

A retrospective study was carried out using the database of hospital admissions to the addiction unit for detoxification from 2003 to 2010.

Results

Of 879 admissions to the addiction unit during the seven-year period, 281 were for benzodiazepines. The percentage of patients addicted only to benzodiazepines was higher among females than males. Benzodiazepine consumption had started as a drug addiction behavior in only 10% of cases. The main sources of prescription identified were general practitioners (52% of cases) or compliant pharmacists (25%). Overall, 15 different benzodiazepines were abused, with lormetazepam being the most commonly used (by 123 patients, 43.8% of the total).

Conclusion

Our data show that, outside the population of multidrug addicts, there is an underestimated group of chronic benzodiazepine consumers who are often not referred to medical institutions for treatment. Even in the group of patients addicted to one substance only, we observed an abnormal number of requests for detoxification from lormetazepam, which appears to be more “popular” than other benzodiazepines. This drug should be prescribed according to stricter criteria and submitted to closer control.