Antithyroid Medication Management for Hyperthyroidism

Medication Selection and Dosage

Carbimazole, a prodrug converted to methimazole, inhibits thyroid hormone synthesis and is rarely used, but may be considered when anti-TSH receptor antibodies are positive in the context of immune-mediated hyperthyroidism 1, 2
The American Society of Clinical Oncology recommends propranolol (or atenolol) for symptomatic relief in all patients with hyperthyroid symptoms, including tachycardia, tremor, anxiety, palpitations, or heat intolerance, regardless of severity grade 1, 2, 3, 4

Beta-blockers, such as propranolol, provide rapid symptomatic control while awaiting thyroid hormone normalization with thionamides, and should be continued until thyroid function normalizes, then tapered as symptoms resolve 1, 2, 3, 4

Thyroid function (TSH, free T4) should be monitored every 2-3 weeks initially to detect transition from hyperthyroidism to hypothyroidism, especially in thyroiditis cases 3, 4, 5
For persistent hyperthyroidism beyond 6 weeks, patients should be referred to endocrinology for additional workup to exclude Graves' disease 3, 4, 5