title: Are calcium-channel blockers effective in the treatment of tardive dyskinesia?
abstract: OBJECTIVE
  To review the data describing the use of calcium-channel blockers in the treatment of tardive dyskinesia (TD).
  
  
  METHODS
  A MEDLINE search of the English-language literature and a bibliographic review of pertinent articles examining the use of calcium-channel blockers in the treatment of TD were performed. Medical Subject Headings (MESH) terms used were calcium-channel blockers, tardive dyskinesia, nifedipine, verapamil, and diltiazem.
  
  
  METHODS
  Relevant case reports, open trials, and controlled studies reporting on the efficacy of calcium-channel blockers for treating TD are reviewed. Appropriate conclusions are drawn from the data and guidelines are suggested for the practitioner.
  
  
  RESULTS
  Studies addressing the efficacy of calcium-channel blockers in the palliative treatment of TD have yielded mixed results. Positive findings have been reported for nifedipine, verapamil, and diltiazem; nifedipine may be the most efficacious treatment and diltiazem the least. It appears that patients with TD who can tolerate higher doses of calcium-channel blockers may respond more favorably to treatment. Patient characteristics that may help determine a better response to treatment with calcium-channel blockers include advanced age and more-severe TD.
  
  
  CONCLUSIONS
  To determine the efficacy of calcium-channel blockers in the treatment of TD, additional data are needed from double-blind, placebo-controlled studies with larger sample sizes and longer durations of treatment. Until these data are available, calcium-channel blockers should be considered potentially useful therapy for the heretofore unresponsive TD.
authors.affiliation: Department of Veterans Affairs Hospital, Salt Lake City, UT 84148.
authors.forename: M
authors.initials: M
authors.lastname: Cates
authors.forename: K
authors.initials: K
authors.lastname: Lusk
authors.forename: B G
authors.initials: BG
authors.lastname: Wells
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002121:Calcium Channel Blockers / Q000627:therapeutic use*; D002986:Clinical Trials as Topic; D004110:Diltiazem / Q000627:therapeutic use; D004409:Dyskinesia, Drug-Induced / Q000188:drug therapy*; D006801:Humans; D009543:Nifedipine / Q000627:therapeutic use; D010166:Palliative Care; D014700:Verapamil / Q000627:therapeutic use
chemical_list: D002121:Calcium Channel Blockers; D014700:Verapamil; D004110:Diltiazem; D009543:Nifedipine