Drug Interaction Report

Atenolol and Dronedarone: Interaction Details

AI-assisted, pharmacist-reviewed · AI content regenerated Jul 15, 2026 · Source data updated Jul 11, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature

Dronedarone

Multaq
+

Atenolol

Tenormin Tenormin®
Dr. Brian Staiger, PharmD, BCPS
Medically reviewed by
Updated Jul 11, 2026
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Interaction severity
Major
Potentially serious — often needs a change or close monitoring.
How we grade severity & evidence

Severity levels

  • Contraindicated: These should generally not be used together.
  • Major: Potentially serious — often needs a change or close monitoring.
  • Moderate: Can be significant — usually manageable with monitoring.
  • Minor: Usually limited clinical impact.

Evidence grades

  • Established: Well documented — supported by controlled studies or strong clinical data.
  • Probable: Good supporting evidence, though not definitively proven.
  • Suspected: Some evidence suggests this interaction, but it is not well established.
  • Possible: Limited or conflicting evidence; the interaction may occur.
  • Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.

Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.

Of 202 documented Atenolol interactions, 35 are rated major — including this one.
Worried about symptoms right now? Contact your pharmacist or prescriber, or call Poison Control at 1-800-222-1222 (US). Call 911 for an emergency.
At a glance + Effects may be stronger
The Bottom Line
Combining dronedarone and atenolol can slow your heart rate too much, so your care team will typically start atenolol low and monitor your heart; keep taking both as prescribed and report dizziness or a slow pulse.

Dronedarone (Multaq) and atenolol (Tenormin) can both slow your heart rate, so taking them together can make your pulse drop lower than it should. Both medicines are used for heart problems, and each one can put the brakes on your heartbeat. When you use them together, that braking effect can add up, and your heart may beat too slowly.

You might notice feeling tired, dizzy, or lightheaded if your heart rate gets too low. The good news is this is very manageable. Your care team will often start the beta blocker at a low dose and check your heart with an ECG before adjusting. Keep taking both as prescribed and let your doctor or pharmacist know if you feel unusually dizzy or slow.

Effect: Additive negative chronotropy leading to increased incidence of bradycardia when dronedarone is combined with beta blockers.

  • Mechanism: Pharmacodynamic (additive AV nodal/heart-rate suppression). Dronedarone is a CYP2D6 inhibitor and increases AUC/Cmax of CYP2D6-substrate beta blockers (propranolol, metoprolol). Note: atenolol is predominantly renally eliminated and is not a significant CYP2D6 substrate, so the PK component is minimal here; the additive bradycardia risk remains.
  • Evidence: Established. Onset: unspecified. Severity: major.
  • Management: Initiate the beta blocker at a low dose and titrate only after tolerability confirmed by ECG. Monitor heart rate and for symptomatic bradycardia.
Onset
unspecified
Evidence
established
Severity
Major

What happens

Increased exposure to some beta blockers and increased incidence of bradycardia

Interaction Deep Dive

The frequency of bradycardia rose when dronedarone was administered together with beta blockers. Furthermore, because dronedarone acts as a CYP2D6 inhibitor, the AUC and Cmax of beta blockers metabolized by CYP2D6 (propranolol, metoprolol) showed marked increases during concurrent use. When the two agents are combined, initiate the beta-blocker at a low dose and raise it only once adequate tolerability has been confirmed via ECG1.

Why it happens (mechanism)

Inhibition of CYP2D6-mediated metabolism of some beta blockers by dronedarone; mechanism on bradycardia unknown

How to manage this interaction

This interaction can be managed safely with the right monitoring. The main concern is that your heart rate may drop too low when these two are combined.

  • Keep taking both medications exactly as prescribed unless your doctor tells you otherwise.
  • Your care team will often start atenolol at a low dose and increase it only after checking that you tolerate it well, sometimes with an ECG. Your dose may need to be adjusted and individualized by your team.
  • Watch for a slow pulse, dizziness, unusual tiredness, or fainting, and report these to your pharmacist or prescriber.

Management is individual — confirm any change with your pharmacist or prescriber.

Common questions

Can I take Atenolol and Dronedarone together?

Combining dronedarone and atenolol can slow your heart rate too much, so your care team will typically start atenolol low and monitor your heart; keep taking both as prescribed and report dizziness or a slow pulse. Always confirm with your pharmacist or prescriber before making any change.

How serious is the Atenolol and Dronedarone interaction?

It is rated major. Potentially serious — often needs a change or close monitoring.

How quickly could this interaction happen?

The documented onset is "unspecified". The timing of this interaction is not well characterized.

How is the Atenolol and Dronedarone interaction managed?

This interaction can be managed safely with the right monitoring. The main concern is that your heart rate may drop too low when these two are combined. Keep taking both medications exactly as prescribed unless your doctor tells you otherwise. Your care team will often start atenolol at a low dose and increase it only after checking that you tolerate it well, sometimes with an ECG. Your dose may n… Management is individual — always follow your own care team's guidance.

How strong is the evidence for this interaction?

The evidence is graded "established". Well documented — supported by controlled studies or strong clinical data.

Questions for your pharmacist

  • Does my dose of Atenolol or Dronedarone need adjusting while I take them together?
  • What symptoms should prompt me to call you or my prescriber right away?
  • Does the timing of my doses matter for this combination?
  • Is there a safer alternative to one of these medications for me?

References (1)

  1. Product Information: MULTAQ(R) oral tablets, dronedarone oral tablets. sanofi-aventis US LLC (per manufacturer), Bridgewater, NJ, 2017. DailyMed
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Beyond drug–drug

These medications also interact with supplements

Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:

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This information is for education, not a substitute for professional medical advice. Do not start, stop, or change any medication without talking to your pharmacist or prescriber.