Drug interactions
Amlodipine + Phenobarbital
Severity: Moderate
Amlodipine and Phenobarbital: 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
Phenobarbital induces CYP3A4 and can reduce amlodipine exposure. This may lead to loss of blood pressure or angina control.
What this interaction means in plain words
Amlodipine and Phenobarbital 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
Enzyme induction of CYP3A4 increases amlodipine clearance.
What to do
Monitor blood pressure and increase the amlodipine dose if needed. Recheck when phenobarbital is changed or stopped.
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
Frequently asked questions
Can I take Amlodipine with Phenobarbital?
MediHelp rates the interaction as moderate. Amlodipine and Phenobarbital 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. Phenobarbital induces CYP3A4 and can reduce amlodipine exposure. This may lead to loss of blood pressure or angina control.
How serious is the interaction between Amlodipine and Phenobarbital?
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 increase the amlodipine dose if needed. Recheck when phenobarbital is changed or stopped.
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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