Drug interactions
Lisinopril + Phentolamine
Severity: Moderate
Lisinopril and Phentolamine: 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
Phentolamine is a non-selective alpha-adrenergic blocker causing vasodilation. With lisinopril, blood pressure can fall more than expected, particularly after the first doses, producing dizziness or fainting.
What this interaction means in plain words
Lisinopril and Phentolamine 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.
Lisinopril belongs to Cardiovascular; Phentolamine belongs to Cardiovascular.
Why it happens
Additive vasodilatory and hypotensive effects of alpha-adrenergic blockade and ACE inhibition.
What to do
Monitor blood pressure closely when the combination is started, with the patient seated or supine for early doses. Lower the dose of one or both agents 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 Lisinopril
- Aliskiren + Lisinopril Contraindicated
- Lisinopril + Protein a column Contraindicated
- Lisinopril + Sacubitril / valsartan Contraindicated
- Lisinopril + Sacubitril-valsartan Contraindicated
- Amifostine + Lisinopril Major
- Amiloride + Lisinopril Major
Other interactions of Phentolamine
Frequently asked questions
Can I take Lisinopril with Phentolamine?
MediHelp rates the interaction as moderate. Lisinopril and Phentolamine 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. Phentolamine is a non-selective alpha-adrenergic blocker causing vasodilation. With lisinopril, blood pressure can fall more than expected, particularly after the first doses, producing dizziness or fainting.
How serious is the interaction between Lisinopril and Phentolamine?
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 closely when the combination is started, with the patient seated or supine for early doses. Lower the dose of one or both agents if hypotension occurs.
What other medicines interact with Lisinopril?
MediHelp also lists interactions of Lisinopril with, for example, Aliskiren, Protein a column, Sacubitril / valsartan. The full list is on the Lisinopril page.
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