Drug interactions
Benazepril + Phenoxybenzamine
Severity: Moderate
Benazepril and Phenoxybenzamine: 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
Phenoxybenzamine causes irreversible alpha-adrenergic blockade and vasodilation. Combined with benazepril it can produce marked hypotension, especially after the first doses or a dose increase.
What this interaction means in plain words
Benazepril and Phenoxybenzamine 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
Alpha-adrenoceptor blockade and ACE inhibition both lower vascular tone, giving additive hypotensive effects.
What to do
Start with low doses and check supine and standing blood pressure after initiation and each dose change. Advise slow position changes and adjust the dose of either drug if orthostatic symptoms occur.
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 Benazepril
- Aliskiren + Benazepril Contraindicated
- Benazepril + Sacubitril / valsartan Contraindicated
- Benazepril + Sacubitril-valsartan Contraindicated
- Amifostine + Benazepril Major
- Amiloride + Benazepril Major
- Amlodipine-hydrochlorothiazide-valsartan + Benazepril Major
Frequently asked questions
Can I take Benazepril with Phenoxybenzamine?
MediHelp rates the interaction as moderate. Benazepril and Phenoxybenzamine 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. Phenoxybenzamine causes irreversible alpha-adrenergic blockade and vasodilation. Combined with benazepril it can produce marked hypotension, especially after the first doses or a dose increase.
How serious is the interaction between Benazepril and Phenoxybenzamine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Start with low doses and check supine and standing blood pressure after initiation and each dose change. Advise slow position changes and adjust the dose of either drug if orthostatic symptoms occur.
What other medicines interact with Benazepril?
MediHelp also lists interactions of Benazepril with, for example, Aliskiren, Sacubitril / valsartan, Sacubitril-valsartan. The full list is on the Benazepril page.
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