Sertraline and Fexinidazole: 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
Fexinidazole
No brand names on recordSertraline
No brand names on record
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.
Both of these medicines can affect the timing of your heartbeat. Fexinidazole (a medicine used for sleeping sickness) and sertraline (an antidepressant) can each stretch out a part of your heart's rhythm called the QT interval. Taken together, that effect can add up and, in rare cases, lead to an irregular heartbeat.
This concern is mostly based on how these drugs work rather than a lot of real-world reports, so try not to worry. The important thing is that your care team can manage this safely. Please don't stop or change either medicine on your own. Just talk with your doctor or pharmacist so they can decide the safest plan for you.
Effect: Additive risk of QT/QTcF interval prolongation with concurrent fexinidazole and sertraline.
Mechanism: Both agents independently prolong the QT interval; combined use is additive (pharmacodynamic, not enzyme-mediated). Neither is a relevant prodrug here.
- Direction: Increased cardiac (PD) effect on repolarization.
- Onset: Unspecified.
- Evidence: Theoretical; severity rated major.
- Management: Avoid concomitant use. If both are needed, separate by washout: allow 5 half-lives of sertraline before starting fexinidazole, or 7 days after fexinidazole before starting the other QT-prolonging drug. Consider ECG and electrolyte (K+, Mg2+) monitoring per clinical judgment.
What happens
An increased risk of QT interval prolongation
Interaction Deep Dive
Do not use fexinidazole together with medications recognized to prolong the QT interval. For patients who are receiving, or who require, agents known to prolong the QTcF interval, one of two approaches should be followed: either delay starting fexinidazole until those agents have cleared the body (permit a washout equal to 5 half-lives of the other drugs), or postpone starting those agents until fexinidazole has cleared the body (permit a 7-day washout for fexinidazole)1.
Why it happens (mechanism)
Additive QT interval prolongation
How to manage this interaction
Your care team will usually try to avoid using these two together because their heart-rhythm effects can add up. If both are truly needed, they typically use a washout gap so only one is in your body at a time.
- Allow about 5 half-lives of sertraline to clear before starting fexinidazole, or
- Allow about 7 days after fexinidazole before starting the other drug.
Keep taking both exactly as prescribed for now, and do not stop either one on your own. Ask your pharmacist or prescriber about the timing plan, and mention any dizziness, fainting, or palpitations. Your team may check an ECG or your electrolytes.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Sertraline and Fexinidazole together?
Fexinidazole and sertraline can each prolong the QT interval, so combining them may raise the risk of an abnormal heart rhythm; this pairing is generally avoided, and your care team may use a washout period or extra monitoring. Do not change either medicine on your own. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Sertraline and Fexinidazole 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 Fexinidazole interaction managed?
Your care team will usually try to avoid using these two together because their heart-rhythm effects can add up. If both are truly needed, they typically use a washout gap so only one is in your body at a time. Allow about 5 half-lives of sertraline to clear before starting fexinidazole, or Allow about 7 days after fexinidazole before starting the other drug. Keep taking both exactly as prescribed… 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 Fexinidazole 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)
- Product Information: Fexinidazole oral tablets, fexinidazole oral tablets. sanofi-aventis US LLC (per FDA), Bridgewater, NJ, 2021. DailyMed
Keep reading about Fexinidazole
Keep reading about Sertraline
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:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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