title: 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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Primary and Community Care, Radboud University Nijmegen Medical Centre, Nijmegen, the Netherlands.
authors.forename: Inge A T
authors.initials: IA
authors.lastname: Willems
authors.forename: Wim J M J
authors.initials: WJ
authors.lastname: Gorgels
authors.forename: Richard C
authors.initials: RC
authors.lastname: Oude Voshaar
authors.forename: Jan
authors.initials: J
authors.lastname: Mulder
authors.forename: Peter L B J
authors.initials: PL
authors.lastname: Lucassen
mesh_terms: D000328:Adult; D014151:Anti-Anxiety Agents / Q000145:classification / Q000494:pharmacology; D001008:Anxiety Disorders / Q000188:drug therapy*; D001569:Benzodiazepines / Q000145:classification / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004361:Drug Tolerance; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D011320:Primary Health Care / Q000379:methods / Q000706:statistics & numerical data; D012893:Sleep Wake Disorders / Q000188:drug therapy*; D019966:Substance-Related Disorders / Q000453:epidemiology / Q000209:etiology*; D013995:Time
chemical_list: D014151:Anti-Anxiety Agents; D001569:Benzodiazepines
keywords: Anxiety/anxiety; abuse (not tobacco).; clinical; disorder; longitudinal; primary care; psychiatry; research; sleep disorders; substance