amiodarone induced hyperthyroidism
Last reviewed 03/2022
- incidence
- in areas with high iodine intake - 1.7%
- in areas with low iodine intake - 12%
- pathogenesis
- type 1 - occurs particularly in patients with underlying thyroid disease; iodine induced excessive synthesis of thyroid hormone
- type 2 - destructive thyroiditis (amiodarone induced); occurs in patients with no previous underlying thyroid disease; thyroiditis results in release of thyroid hormones into the circulation
- diagnosis
- suppressed TSH levels; increased T3 and T4
- fine needle aspiration - will yield evidence of thyroiditis
- treatment
- if possible withdrawal of amiodarone - note that withdrawal has no immediate effect because of very long half life of amiodarone
- type 1 - first line therapy is use of antithyroid drugs; steroid treatment may be used in addition
- type 2 - steroid treatment