Drug interactions
Amlodipine + Phentolamine
Severity: Moderate
Amlodipine 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 that causes vasodilation, and combined with amlodipine it can produce marked hypotension and reflex tachycardia. The risk is greatest with parenteral phentolamine.
What this interaction means in plain words
Amlodipine 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.
Amlodipine belongs to Cardiovascular; Phentolamine belongs to Cardiovascular.
Why it happens
Additive vasodilation from alpha-adrenergic blockade and calcium channel blockade.
What to do
Monitor blood pressure and heart rate closely, particularly after parenteral phentolamine. Reduce doses if symptomatic 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 Amlodipine
- Amifostine + Amlodipine Major
- Amlodipine + Ombitasvir / paritaprevir / ritonavir and dasabuvir Major
- Activated Charcoal + Amlodipine Moderate
- Aldesleukin + Amlodipine Moderate
- Alfuzosin + Amlodipine Moderate
- Amlodipine + Apalutamide Moderate
Other interactions of Phentolamine
Frequently asked questions
Can I take Amlodipine with Phentolamine?
MediHelp rates the interaction as moderate. Amlodipine 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 that causes vasodilation, and combined with amlodipine it can produce marked hypotension and reflex tachycardia. The risk is greatest with parenteral phentolamine.
How serious is the interaction between Amlodipine 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 and heart rate closely, particularly after parenteral phentolamine. Reduce doses if symptomatic hypotension occurs.
What other medicines interact with Amlodipine?
MediHelp also lists interactions of Amlodipine with, for example, Amifostine, Ombitasvir / paritaprevir / ritonavir and dasabuvir, Activated Charcoal. The full list is on the Amlodipine page.
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