Drug interactions
Bretylium + Hydrochlorothiazide
Severity: Moderate
Bretylium and Hydrochlorothiazide: 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
Bretylium causes orthostatic hypotension through adrenergic neuron blockade, and a thiazide diuretic can add to this through volume depletion. The combination may produce excessive hypotension.
What this interaction means in plain words
Bretylium and Hydrochlorothiazide 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 from sympathetic blockade and diuretic-induced volume and sodium depletion.
What to do
Monitor blood pressure including standing readings, and correct volume depletion. Reduce the diuretic dose if hypotension occurs.
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 Hydrochlorothiazide
Frequently asked questions
Can I take Bretylium with Hydrochlorothiazide?
MediHelp rates the interaction as moderate. Bretylium and Hydrochlorothiazide 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. Bretylium causes orthostatic hypotension through adrenergic neuron blockade, and a thiazide diuretic can add to this through volume depletion. The combination may produce excessive hypotension.
How serious is the interaction between Bretylium and Hydrochlorothiazide?
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 including standing readings, and correct volume depletion. Reduce the diuretic dose if hypotension occurs.
What other medicines interact with Hydrochlorothiazide?
MediHelp also lists interactions of Hydrochlorothiazide with, for example, Dofetilide, Amifostine, Amiodarone. The full list is on the Hydrochlorothiazide page.
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