title: Two cases of statin-induced myopathy caused by induced hypothyroidism.
abstract: OBJECTIVE
  To present information regarding the potential danger of performing levothyroxine withdrawal radioiodine scans and treatment in patients with thyroid cancer who are concurrently taking lipid-lowering agents.
  
  
  METHODS
  We review the clinical history, serial laboratory data, and radiologic findings in 2 patients with multifocal papillary carcinoma of the thyroid.
  
  
  RESULTS
  Both study patients had substantial elevations of muscle enzymes or myopathies (or both) when they were withdrawn from levothyroxine therapy, during treatment with lipid-lowering agents, in preparation for radioiodine scanning and treatment.
  
  
  CONCLUSIONS
  Extreme caution should be exercised when levothyroxine therapy is withdrawn from patients taking lipid-lowering agents. Such patients should be monitored very closely or, when appropriate, recombinant human thyroid-stimulating hormone injections should be used rather than levothyroxine withdrawal in this setting.
authors.affiliation: Department of Medicine, George Washington University, Alexandria, VA 22306, USA.
authors.forename: Howard M
authors.initials: HM
authors.lastname: Lando
authors.forename: Kenneth D
authors.initials: KD
authors.lastname: Burman
mesh_terms: D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000008:administration & dosage / Q000009:adverse effects*; D007037:Hypothyroidism / Q000139:chemically induced*; D007457:Iodine Radioisotopes / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009135:Muscular Diseases / Q000139:chemically induced*; D019821:Simvastatin / Q000008:administration & dosage / Q000009:adverse effects*; D013964:Thyroid Neoplasms / Q000188:drug therapy / Q000532:radiotherapy; D013974:Thyroxine / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use
chemical_list: D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D007457:Iodine Radioisotopes; D019821:Simvastatin; D013974:Thyroxine