Propranolol vs. Metoprolol for Hyperthyroidism with Palpitations

Mechanism of Action Differences

• Propranolol is superior to metoprolol for treating hyperthyroidism with palpitations due to its non-selective beta-blocking properties that not only control heart rate but also inhibit peripheral conversion of T4 to T3, according to the American Heart Association 1, 2

Guideline Recommendations

• The European Society of Cardiology recommends beta-blockers for controlling ventricular rate in patients with AF complicating thyrotoxicosis, with propranolol being the most widely studied non-selective beta-blocker for hyperthyroidism 3, 4, 5, 1, 2
• The American College of Cardiology suggests that propranolol is particularly important for thyroid storm (severe hyperthyroidism) and may require high doses 5, 6

Special Considerations

• In severe hyperthyroidism or thyroid storm, propranolol's dual action (rate control and inhibition of T4 to T3 conversion) makes it particularly valuable, as recommended by the European Heart Association 5, 2