What medications cannot be taken with amlodipine?

October 11, 2025 •

3 min read

Over 47% of US adults have high blood pressure, and many are prescribed amlodipine, a common medication to manage the condition. However, amlodipine is extensively metabolized by the liver enzyme CYP3A4, making it susceptible to significant interactions with other drugs that either inhibit or induce this enzyme. Therefore, understanding what medications cannot be taken with amlodipine is crucial for preventing dangerous side effects and ensuring treatment effectiveness.

Quick Summary

Amlodipine interacts with several medications by affecting liver enzymes, increasing risks of hypotension, toxicity, or reduced efficacy. Key interactions include certain statins, antibiotics, antifungals, erectile dysfunction drugs, and immunosuppressants. Grapefruit juice should also be avoided, as it can increase amlodipine's effects.

Key Points

Statins: Caution is advised with simvastatin and lovastatin when taken with amlodipine due to increased risk of muscle damage (myopathy, rhabdomyolysis).
Grapefruit: Limit or avoid grapefruit and grapefruit juice, as they can significantly increase amlodipine levels and enhance side effects.
Antibiotics: Caution is needed with macrolides like clarithromycin (can increase amlodipine levels) and rifampin (can decrease effectiveness).
Erectile Dysfunction Drugs: Combining PDE5 inhibitors like sildenafil or tadalafil with amlodipine can cause a dangerous drop in blood pressure.
Antifungals and Immunosuppressants: Azole antifungals (ketoconazole, itraconazole) and immunosuppressants (cyclosporine, tacrolimus) can significantly alter drug levels when taken with amlodipine.
Over-the-Counter Remedies: Be cautious with cold medications containing pseudoephedrine or nasal decongestants, as they can counteract amlodipine's blood pressure-lowering effect.
Other Blood Pressure Medications: Combinations with other antihypertensives, such as beta-blockers, require close monitoring due to additive effects on blood pressure.

Amlodipine, a widely used calcium channel blocker, is an effective treatment for hypertension and angina. Its therapeutic benefits, however, can be undermined or dangerously amplified by concurrent use of other medications, foods, and supplements. These interactions primarily occur because amlodipine's breakdown in the body relies on the cytochrome P450 3A4 (CYP3A4) enzyme system in the liver. Drugs or substances that inhibit this enzyme can increase amlodipine levels, while those that induce it can decrease amlodipine's effectiveness.

High-Risk Drug Categories with Amlodipine

Cholesterol-Lowering Medications (Statins)

Amlodipine can significantly raise the blood levels of certain statin medications, increasing the risk of serious side effects, such as myopathy and rhabdomyolysis. Simvastatin and lovastatin are particularly affected. Safer statin alternatives include atorvastatin, rosuvastatin, or pravastatin.

Erectile Dysfunction Medications (PDE5 Inhibitors)

Combining amlodipine with PDE5 inhibitors like sildenafil (Viagra) or tadalafil (Cialis) can cause a significant drop in blood pressure (hypotension) due to their combined vasodilating effects. This can lead to dizziness, fainting, or headaches.

Antifungal Medications (Azole Antifungals)

Azole antifungals, such as ketoconazole and itraconazole, inhibit the enzyme that metabolizes amlodipine, increasing its levels in the body. This can enhance amlodipine's effects and increase the risk of severe hypotension and fluid retention.

Antibiotics

Certain antibiotics like clarithromycin and erythromycin can increase amlodipine levels, raising the risk of excessive hypotension, particularly in older adults. Rifampin, however, is an enzyme inducer that can decrease amlodipine levels, reducing its effectiveness. Azithromycin is an alternative antibiotic that generally doesn't interact with amlodipine.

Immunosuppressants

Amlodipine can increase the levels of immunosuppressants like cyclosporine and tacrolimus, potentially increasing the risk of side effects.

Other Notable Interactions

Long-term use of NSAIDs can increase blood pressure, counteracting amlodipine. St. John's Wort can decrease amlodipine levels. Grapefruit and grapefruit juice can increase amlodipine levels and side effects. Decongestants can raise blood pressure. Combining amlodipine with general anesthetics or other blood pressure medications (other calcium channel blockers, beta-blockers, MAOIs) can lead to excessive blood pressure drops.

Comparison of High-Risk Amlodipine Combinations


Drug Category	Specific Examples	Potential Effect	Management
Statins	Simvastatin, Lovastatin	Increased statin levels, myopathy, rhabdomyolysis.	Consider alternative statin or dose adjustments under medical supervision.
PDE5 Inhibitors	Sildenafil (Viagra), Tadalafil	Additive hypotensive effect, risk of severe low blood pressure.	Cautious monitoring and dose adjustment; avoid rising too quickly.
Azole Antifungals	Ketoconazole, Itraconazole	Increased amlodipine levels, enhanced hypotensive effects.	Dose adjustment of amlodipine under medical supervision; monitor for symptoms.
Macrolide Antibiotics	Clarithromycin, Erythromycin	Increased amlodipine levels, excessive hypotension, kidney issues.	Use alternative antibiotic (azithromycin); monitor closely.
Tuberculosis Drug	Rifampin	Decreased amlodipine levels, reduced effectiveness.	Dose adjustment of amlodipine or use alternative antihypertensive under medical supervision.
Immunosuppressants	Cyclosporine, Tacrolimus	Increased immunosuppressant levels, higher risk of toxicity.	Dose adjustment of immunosuppressant; close monitoring.
Grapefruit Juice	All grapefruit products	Increased amlodipine levels, enhanced side effects.	Limit or avoid consumption of grapefruit products.
NSAIDs (Chronic Use)	Ibuprofen, Naproxen	Increased blood pressure, counteracting amlodipine's effect.	Occasional use is fine; discuss long-term use with doctor.

Potential Risks of Amlodipine Drug Interactions

Interactions can lead to severe hypotension, increased toxicity of other medications (like statins or immunosuppressants), reduced amlodipine effectiveness (with enzyme inducers), or additive hypotensive effects when combined with other blood pressure-lowering drugs. Grapefruit juice can increase amlodipine levels, and combining amlodipine with general anesthetics carries a risk of extremely low blood pressure during surgery. Patients should be aware of symptoms of increased amlodipine effects, such as swelling or dizziness.

Avoiding Amlodipine Interactions

To avoid interactions, maintain a complete list of all medications and supplements for your healthcare provider. Always consult your doctor or pharmacist before starting new drugs. Pay attention to new or worsening side effects. Your doctor may consider alternative medications or adjust doses. Be mindful of interactions with food and alcohol, especially grapefruit.

Conclusion: Safe Medication Management

Managing amlodipine safely requires open communication with your healthcare team about all medications and supplements you are taking. Awareness of potential interactions, particularly with certain statins, antifungals, antibiotics, and lifestyle factors like grapefruit consumption, is key to preventing serious complications. Always seek professional guidance to ensure your amlodipine treatment is both safe and effective. For more information, the National Institutes of Health (NIH) provides resources on drug interactions related to enzyme metabolism.

Frequently Asked Questions

Yes, but with caution and under a doctor's supervision. Your doctor will consider the appropriate approach to minimize the risk of serious muscle-related side effects like myopathy or rhabdomyolysis. Your doctor might also recommend an alternative statin.

Yes, grapefruit and its juice can interact with amlodipine. It inhibits the CYP3A4 enzyme responsible for amlodipine metabolism, leading to higher levels of the medication in your bloodstream and an increased risk of side effects like dizziness, flushing, or headache.

Taking sildenafil and amlodipine together can cause a dangerous and excessive drop in blood pressure (hypotension). Both medications lower blood pressure by relaxing blood vessels, and their combined effect can be too strong. Consult your doctor for safe management.

Combining amlodipine with clarithromycin is generally not recommended, especially for older adults. Clarithromycin can inhibit the enzyme that breaks down amlodipine, leading to increased amlodipine levels and a higher risk of severe low blood pressure and kidney issues.

Yes, you should avoid or be cautious with over-the-counter cold medications containing decongestants like pseudoephedrine or oxymetazoline. These ingredients can raise blood pressure, which can counteract the effects of your amlodipine.

Yes, St. John's Wort, an herbal supplement often used for depression, is known to interact with amlodipine. It induces the CYP3A4 enzyme, which can lower the amount of amlodipine in your blood and make it less effective at controlling your blood pressure.

While it is not strictly prohibited, excessive alcohol consumption can have an additive effect in lowering your blood pressure, which could cause dizziness, fainting, or headaches. It is best to limit alcohol intake and monitor how it affects you.