title: Drug-associated headache is unrecognized in patients treated at a neurological centre.
abstract: OBJECTIVE
  We studied the frequency of unrecognized headache associated with overuse of analgesic drugs in a population of headache patients treated at a neurological centre.
  
  
  METHODS
  Patients in North Norway referred to a neurologist for headache during a 2-year period completed a questionnaire. From a total of 945, 262 patients (28%) reported headache 3 days or more per week and used analgesic drugs on a daily bases.
  
  
  RESULTS
  A specific diagnoses given by the neurologist was reported in 134 of the patients (51%). Only two patients reported that they suffered from a possible drug-associated headache.
  
  
  CONCLUSIONS
  This study shows that drug overuse may be the cause of chronic headache in more than 1/4 patients referred to neurologists. Drug-associated headache is a difficult diagnosis which deserves more attention because it is a common and treatable condition.
authors.affiliation: Department of Neurology, Tromsø University Hospital, Tromsø, Norway. nevrsib@rito.no
authors.forename: S I
authors.initials: SI
authors.lastname: Bekkelund
authors.forename: R
authors.initials: R
authors.lastname: Salvesen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000700:Analgesics / Q000008:administration & dosage* / Q000009:adverse effects*; D002648:Child; D002908:Chronic Disease; D003951:Diagnostic Errors / Q000706:statistics & numerical data*; D005260:Female; D006261:Headache / Q000139:chemically induced* / Q000175:diagnosis / Q000453:epidemiology*; D006748:Hospital Departments / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009462:Neurology / Q000706:statistics & numerical data*; D009664:Norway / Q000453:epidemiology; D018570:Risk Assessment / Q000706:statistics & numerical data
chemical_list: D000700:Analgesics