title: Dramatic response to cholestyramine in a patient with Graves' disease resistant to conventional therapy.
abstract: BACKGROUND
  Resistance to the conventional treatment of hyperthyroidism with antithyroid drugs is not commonly found in clinical practice, and only few other treatment options have been reported on in detail. For example, surgery or radioiodine ablation are well-accepted interventions that must be always considered. The euthyroid state is strongly recommended before both of these as this might reduce complications. There are few studies indicating that bile acid sequestrants, when added to antithyroid drugs, produce a more rapid decline in serum thyroid hormone levels and that this effect is maintained for at least 4 weeks. Complete normalization of serum thyroid hormone levels is generally not expected, however.
  
  
  CONCLUSIONS
  We report a patient whose thyrotoxicosis failed to respond to conventional treatment. The patient remained persistently hyperthyroid, both clinically and biochemically, despite several months of methimazole and propranolol and the addition of iodine. Cholestyramine, a bile acid sequestrant, was then added, and a dramatic improvement was observed.
  
  
  CONCLUSIONS
  We report a patient who was resistant to conventional antithyroid drugs in whom thyroid hormone levels completely normalized after 1 week of additional treatment with cholestyramine.
authors.affiliation: Department of Endocrinology, University Hospital San Cecilio, Granada, Spain. arantzazuso@hotmail.com
authors.forename: Arántzazu
authors.initials: A
authors.lastname: Sebastián-Ochoa
authors.forename: Miguel
authors.initials: M
authors.lastname: Quesada-Charneco
authors.forename: Diego
authors.initials: D
authors.lastname: Fernández-García
authors.forename: Rebeca
authors.initials: R
authors.lastname: Reyes-García
authors.forename: Pedro
authors.initials: P
authors.lastname: Rozas-Moreno
authors.forename: Fernando
authors.initials: F
authors.lastname: Escobar-Jiménez
mesh_terms: D000328:Adult; D013956:Antithyroid Agents / Q000627:therapeutic use*; D002792:Cholestyramine Resin / Q000627:therapeutic use*; D004351:Drug Resistance; D004359:Drug Therapy, Combination; D004535:Ehlers-Danlos Syndrome / Q000150:complications; D005260:Female; D006111:Graves Disease / Q000188:drug therapy*; D006801:Humans; D007455:Iodine / Q000627:therapeutic use; D008713:Methimazole / Q000627:therapeutic use; D011433:Propranolol / Q000627:therapeutic use; D016896:Treatment Outcome
chemical_list: D013956:Antithyroid Agents; D002792:Cholestyramine Resin; D008713:Methimazole; D007455:Iodine; D011433:Propranolol