Liothyronine and Propranolol interaction
Liothyronine and Propranolol: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Propranolol (InnoPran XL) label · effective 2026-08-27
Avoid abrupt withdrawal of beta-blockade, which may precipitate a thyroid storm.
From the Liothyronine (Liothyronine Sodium) label · effective 2026-06-04
Drug or Drug Class Effect Beta-adrenergic antagonists (e.g., Propranolol >160 mg/day) In patients treated with large doses of propranolol (>160 mg/day), T3 and T4 levels change, TSH levels remain normal, and patients are clinically euthyroid.
Actions of particular beta-adrenergic antagonists may be impaired when a hypothyroid patient is converted to the euthyroid state.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.