What the FDA labels say about taking them together
Betaxolol and diltiazem
Betaxolol's FDA label of December 20, 2023 names diltiazem in its drug interactions section; diltiazem's label does not name betaxolol itself but warns about its class (Beta blockers). The betaxolol label: “… complete heart block, were more likely to occur with either verapamil or diltiazem.”
Check it at the source: the betaxolol FDA label on DailyMed (effective December 20, 2023, Epic Pharma LLC); the diltiazem FDA label on DailyMed (effective August 7, 2026, Bausch Health US, LLC).
What does the betaxolol label say about diltiazem?
Betaxolol label, drug interactionsHypotension was more likely to occur if the calcium antagonist were a dihydropyridine derivative, eg, nifedipine, while left ventricular failure and AV conduction disturbances, including complete heart block, were more likely to occur with either verapamil or diltiazem.
Source: FDA drug label (Betaxolol), Epic Pharma LLC, effective December 20, 2023 (SPL set bf716efe-0a9f-43b1-9d8a-c69330b82e18), via openFDA; the full label on DailyMed
What does the diltiazem label say about betaxolol?
Diltiazem's label does not name betaxolol itself; it warns about its class (Beta blockers):
Diltiazem label, drug interactionsBeta-blockers, digitalis, and other agents known to impair cardiac contractility and conduction may increase risk for hypotension, bradycardia, and heart failure.
Diltiazem label, drug interactionsPharmacologic studies indicate that there may be additive effects in prolonging AV conduction when using beta-blockers or digitalis concomitantly with Tiazac (see WARNINGS ).
Source: FDA drug label (TIAZAC EXTENDED RELEASE), Bausch Health US, LLC, effective August 7, 2026 (SPL set c567fe7e-887e-4291-a0d1-2dd3f25cbf25), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Betaxolol | Diltiazem | |
|---|---|---|
| Labeled for | High blood pressure, Glaucoma | High blood pressure, Angina, Atrial fibrillation |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $0.591 per tablet 10 mg tablet | $0.144 per capsule 24h ER(cd) 120 mg capsule |
| Shortage now | No current entry | A presentation being discontinued |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once