title: Medication-induced headache: overview and systematic review of therapeutic approaches.
abstract: OBJECTIVE
  To review medication-induced headache (MIH) through a systematic evaluation of the literature regarding the pharmacologic management of this condition.
  
  
  METHODS
  To identify and evaluate all pharmacologic interventions for MIH, we conducted a qualitative systematic review of the English-language literature from 1966 to June 1998 using MEDLINE. The following search terms were used: chronic daily headache, transformed migraine, analgesic withdrawal headache, analgesic rebound headache, drug-associated headache, medication-induced headache, detoxification, and dihydroergotamine. In addition, a review of the references from relevant literature was also conducted to collect reports not identified in the MEDLINE search.
  
  
  RESULTS
  Numerous therapies for acute management of MIH have been evaluated, although no rigorously conducted clinical trials were identified. Therapies evaluated include abrupt withdrawal of analgesics, initiation of dihydroergotamine, nonsteroidal antiinflammatory agents, methylergonovine, dihydroergotamine, sumatriptan, amitriptyline, dexamethasone, piracetam, prothipendyl, and valproate. Epidemiology, diagnosis, clinical features, pathophysiology, and long-term prognosis of therapy are discussed and therapeutic guidelines are offered.
  
  
  CONCLUSIONS
  MIH is an underrecognized and difficult condition affecting headache-prone patients. The published literature concerning treatment of patients with MIH is scant and of poor quality, making it difficult for clinicians to decide on appropriate therapy. Recognition and treatment of MIH may lead to a long-term improvement in headache relief for many patients. It appears that complete withdrawal of the medications being overused is required for favorable long-term results.
authors.affiliation: Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, Canada.
authors.forename: P J
authors.initials: PJ
authors.lastname: Zed
authors.forename: P S
authors.initials: PS
authors.lastname: Loewen
authors.forename: G
authors.initials: G
authors.lastname: Robinson
mesh_terms: D000639:Amitriptyline / Q000627:therapeutic use; D000700:Analgesics / Q000627:therapeutic use; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use; D002908:Chronic Disease; D004873:Ergolines / Q000627:therapeutic use; D006261:Headache / Q000139:chemically induced / Q000188:drug therapy / Q000453:epidemiology / Q000628:therapy*; D006801:Humans; D016239:MEDLINE; D010889:Piracetam / Q000627:therapeutic use; D016032:Randomized Controlled Trials as Topic; D013375:Substance Withdrawal Syndrome / Q000503:physiopathology; D018170:Sumatriptan / Q000627:therapeutic use; D013843:Thiazines / Q000627:therapeutic use; D014635:Valproic Acid / Q000627:therapeutic use