Drug interactions
Bretylium + Diltiazem
Severity: Moderate
Bretylium and Diltiazem: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Both drugs can cause hypotension, and bretylium often produces orthostatic hypotension. Combined use may worsen blood pressure drops.
What this interaction means in plain words
Bretylium and Diltiazem can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Why it happens
Additive hypotensive effects: calcium channel blockade vasodilation plus adrenergic neuron blockade.
What to do
Monitor blood pressure frequently during bretylium therapy and keep the patient supine. Reduce or hold diltiazem if hypotension develops.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Diltiazem
- Diltiazem + Flibanserin Contraindicated
- Diltiazem + Ivabradine Contraindicated
- Diltiazem + Lomitapide Contraindicated
- Diltiazem + Lonafarnib Contraindicated
- Acebutolol + Diltiazem Major
- Alfentanil + Diltiazem Major
Frequently asked questions
Can I take Bretylium with Diltiazem?
MediHelp rates the interaction as moderate. Bretylium and Diltiazem can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Both drugs can cause hypotension, and bretylium often produces orthostatic hypotension. Combined use may worsen blood pressure drops.
How serious is the interaction between Bretylium and Diltiazem?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor blood pressure frequently during bretylium therapy and keep the patient supine. Reduce or hold diltiazem if hypotension develops.
What other medicines interact with Diltiazem?
MediHelp also lists interactions of Diltiazem with, for example, Flibanserin, Ivabradine, Lomitapide. The full list is on the Diltiazem page.
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