Sertraline and Propafenone: Interaction Details
AI-assisted, pharmacist-reviewed · AI content regenerated Jul 11, 2026 · Source data updated Jul 2, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Sertraline
No brand names on recordPropafenone
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.
Here's what's going on. Propafenone (Rythmol) is a heart rhythm medicine. Your body clears it using a liver enzyme called CYP2D6. Sertraline can slow that enzyme down, so propafenone may build up in your blood to higher levels than expected.
Both medicines can also affect the heart's electrical timing (called the QT interval). Together, that could raise the chance of an irregular or dangerous heartbeat. This concern is based on how the drugs work rather than lots of real-world cases, but because it involves the heart, it's taken seriously. Please don't stop or change anything on your own. Your doctor or pharmacist can look at whether these two fit together safely for you.
Mechanism: Sertraline inhibits CYP2D6, the primary enzyme metabolizing propafenone (an active drug, not a prodrug). This reduces clearance and increases propafenone exposure (AUC/Cmax), raising the risk of proarrhythmia. Additive QT-interval prolongation is also expected.
- Direction: increased propafenone effect and toxicity
- Severity: major; evidence: theoretical; onset: unspecified
- Management: Avoidance of the combination is advised. If co-use is unavoidable, the propafenone dose should be individualized by the care team, with closer monitoring including ECG (QTc), heart rate/rhythm, and signs of proarrhythmia. Consider correcting electrolytes and reviewing other QT-prolonging agents.
What happens
Increased propafenone exposure and risk toxicity (cardiac arrhythmias) and an increased risk of QT interval prolongation
Interaction Deep Dive
Giving propafenone together with a CYP2D6 inhibitor like sertraline can raise propafenone exposure and heighten the potential for toxicity, such as proarrhythmia2 and QT prolongation. The combined use of sertraline and propafenone should be avoided, because it may lead to a greater risk of QT prolongation and/or ventricular arrhythmias 1.
Why it happens (mechanism)
Inhibition of CYP2D6-mediated propafenone metabolism; additive QT interval prolongation
How to manage this interaction
The good news is this is manageable. Keep taking both medicines exactly as prescribed unless your prescriber tells you otherwise.
- Tell your doctor and pharmacist that you take both sertraline and propafenone so they can review the combination. Guidance often favors avoiding it, but your team decides what's right for you.
- If they keep both, your propafenone dose may be adjusted and individualized, and your team may monitor you more closely, including heart tracings (ECG).
- Report palpitations, a racing or irregular heartbeat, dizziness, or fainting right away.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Sertraline and Propafenone together?
Combining sertraline and propafenone can raise propafenone levels and the risk of heart rhythm problems, so this pairing is often avoided; ask your doctor or pharmacist to review it and don't change anything on your own. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Sertraline and Propafenone 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 Sertraline and Propafenone interaction managed?
The good news is this is manageable. Keep taking both medicines exactly as prescribed unless your prescriber tells you otherwise. Tell your doctor and pharmacist that you take both sertraline and propafenone so they can review the combination. Guidance often favors avoiding it, but your team decides what's right for you. If they keep both, your propafenone dose may be adjusted and individualized,… Management is individual — always follow your own care team's guidance.
How strong is the evidence for this interaction?
The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Sertraline or Propafenone 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 (2)
- Product Information: ZOLOFT oral tablets, oral solution, sertraline hydrochloride oral tablets, oral solution. Viatris Specialty LLC (per FDA), Morgantown, WV, 2023. DailyMed
- Product Information: RYTHMOL(R) oral tablets, propafenone HCl oral tablets. GlaxoSmithKline (per FDA), Research Triangle Park, NC, 2013. DailyMed
Keep reading about Sertraline
Keep reading about Propafenone
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Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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