Timolol and Verapamil interaction
Timolol and Verapamil: 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 Timolol (Timolol Maleate) label · effective 2024-11-04
Oral or intravenous calcium antagonists may cause atrioventricular conduction disturbances, left ventricular failure, and hypotension.
Digitalis and calcium antagonists may have additive effects in prolonging atrioventricular conduction time.
Calcium Antagonists Caution should be used in the co-administration of beta-adrenergic blocking agents, such as Timolol Maleate Ophthalmic Solution, and oral or intravenous calcium antagonists because of possible atrioventricular conduction disturbances, left ventricular failure, and hypotension.
Digitalis and Calcium Antagonists The concomitant use of beta-adrenergic blocking agents with digitalis and calcium antagonists may have additive effects in prolonging atrioventricular conduction time.
From the Verapamil (Verapamil Hydrochloride) label · effective 2025-03-25
Beta blockers: reports of excess bradycardia and AV block, including complete heart block; monitor closely ( 7.4 )
Beta Blockers Concomitant therapy with beta-adrenergic blockers and verapamil may result in additive negative effects on heart rate, atrioventricular conduction, and/or cardiac contractility.
Antihypertensive Agents Verapamil administered concomitantly with oral antihypertensive agents (e.g., vasodilators, angiotensin-converting enzyme inhibitors, diuretics, beta blockers) will usually have an additive effect on lowering blood pressure.
Avoid verapamil in patients with severe left ventricular dysfunction (e.g., ejection fraction less than 30% or moderate to severe symptoms of cardiac failure) and in patients with any degree of ventricular dysfunction if they are receiving a beta-adrenergic blocker [see Drug Interactions ( 7.4 )].
The combination of extended-release verapamil and beta-adrenergic blocking agents has not been studied.
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.