Atenolol and Quinidine interaction
Atenolol and Quinidine: both prescribing labels describe an interaction that usually calls for monitoring, a dose change, or spacing the doses.
Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.
What the FDA labels say
From the Atenolol (TENORMIN) label · effective 2025-09-18
Amiodarone is an antiarrhythmic agent with negative chronotropic properties that may be additive to those seen with beta-blockers.
Disopyramide is a Type I antiarrhythmic drug with potent negative inotropic and chronotropic effects.
From the Quinidine (Quinidine Gluconate) label · effective 2024-08-27
The effects (if any) of coadministration of other β-blockers on quinidine pharmacokinetics have not been adequately studied.
Coadministration of propranolol usually does not affect quinidine pharmacokinetics, but in some studies the β-blocker appeared to cause increases in the peak serum levels of quinidine, decreases in quinidine's volume of distribution, and decreases in total quinidine clearance.
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.