Metoprolol hormonal

Beta blockers without intrinsic sympathomimetic activity (eg, metoprolol, propranolol, atenolol) are effective therapeutic adjuncts in the management of thyrotoxicosis since many of these symptoms mimic those associated with sympathetic stimulation. Propranolol has been the 3 blocker most widely studied and used in the therapy of thyrotoxicosis. Beta blockers cause clinical improvement of hyperthyroid symptoms but do not typically alter thyroid hormone levels. Propranolol at doses greater than 160 mg/d may also reduce T3 levels approximately 20% by inhibiting the peripheral conversion of T4 to T3. 

Ostman J, Amer P, Haglund K, Juhlin-Dannfelt A, Nowak J, Wennlund A. Effect of metoprolol and alprenolol cn the metabolic, hormonal, and haemortynamic re x>nse to insulin-induced l poglycaemia in hypertensive, insulin-dependent diabetics. Acta Med Scand ( 9 2) 211,381-5. 

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