Two cases of statin-induced myopathy caused by induced hypothyroidism.
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Both study patients had substantial elevations of muscle enzymes or myopathies (or both) when they were withdrawn from levothyroxine therapy, during treatment with lipid-lowering agents, in preparation for radioiodine scanning and treatment.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Extreme caution should be exercised when levothyroxine therapy is withdrawn from patients taking lipid-lowering agents.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.
Lando
Howard M
HM
Department of Medicine, George Washington University, Alexandria, VA 22306, USA.
Burman
Kenneth D
KD
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
D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D007457:Iodine Radioisotopes; D019821:Simvastatin; D013974:Thyroxine