Tolerance to benzodiazepines among long-term users in primary care

Abstract

Background. Tolerance towards the effects of benzodiazepines is observed in various animal and human studies. Therefore, it is assumed that patients who use benzodiazepines for a longer period of time need to increase their dose over time to experience the same effect. Objective. To observe whether long-term benzodiazepine users increase their dose over time. Methods. From the Dutch National Information Network of Family Practices, a group of long-term benzodiazepine users was identified. This group was divided into an incident long-term benzodiazepine users group (N = 113) and a prevalent long-term benzodiazepine users group (N = 992). Long-term use of benzodiazepines was defined as usage for at least 6 months. The main outcome was a change in prescribed dose from baseline until 24 months after baseline. Linear regression analysis was performed to evaluate dose change. Results. Neither incident long-term benzodiazepine users nor prevalent long-term benzodiazepine users were prescribed increasing dosages during follow-up. Conclusion. There is no increase in prescribed dose among long-term users, as might be expected due to the development of tolerance to the effects of benzodiazepines. © The Author 2013. Published by Oxford University Press. All rights reserved.