title: Optimal management of amiodarone therapy: efficacy and side effects.
abstract: OBJECTIVE
  To review management and dosing guidelines for amiodarone therapy, and discuss the drug's adverse event profile.
  
  
  METHODS
  Review of relevant studies and reports.
  
  
  RESULTS
  Amiodarone is a highly effective antiarrhythmic drug, but is associated with adverse effects involving several organs. Amiodarone-induced arrhythmia is rare, with frequency of 0.3% in one study. Pulmonary toxicity is the most serious noncardiac side effect (2-17% of patients). Hypersensitivity pneumonitis can appear early in the course of therapy. Interstitial pneumonitis is a more common but insidious pulmonary reaction characterized by cough, low-grade fever, and dyspnea that occurs after months or years of therapy. Clinically important hypothyroidism and hyperthyroidism occur in 2-10% of patients. Optic neuritis or neuropathy in which patients experience decreased or blurred vision may progress to permanent blindness. Abnormalities in liver function tests, especially elevated aminotransferase and alkaline phosphatase levels, are seen in 4-25% of patients. Neurologic side effects were reported in 20-40% of patients, at times associated with tremor, ataxia, peripheral neuropathy, malaise or fatigue, sleep disturbances, dizziness, and headaches. Several types of dermatologic reactions have been reported, including allergic rash, photosensitivity, and blue-gray skin discoloration. The best strategy for early detection of pulmonary toxicity is vigilant clinical follow-up with monitoring of cardiac status and liver and thyroid function, and prescription of the lowest effective dosage. After an initial loading dose, 200 mg/day in many patients maintains arrhythmia control and minimizes the frequency of side effects.
  
  
  CONCLUSIONS
  Amiodarone is a safe and efficacious antiarrhythmic agent when lower dosages are given to patients who are closely monitored and subject to careful follow-up.
authors.affiliation: Department of Pharmacy Practice, Creighton University School of Pharmacy, Omaha, Nebraska, USA.
authors.forename: D
authors.initials: D
authors.lastname: Hilleman
authors.forename: M A
authors.initials: MA
authors.lastname: Miller
authors.forename: R
authors.initials: R
authors.lastname: Parker
authors.forename: P
authors.initials: P
authors.lastname: Doering
authors.forename: J A
authors.initials: JA
authors.lastname: Pieper
mesh_terms: D000638:Amiodarone / Q000009:adverse effects* / Q000627:therapeutic use*; D000889:Anti-Arrhythmia Agents / Q000009:adverse effects* / Q000627:therapeutic use*; D006801:Humans
chemical_list: D000889:Anti-Arrhythmia Agents; D000638:Amiodarone