Sertraline and Tolterodine: 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 recordTolterodine
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.
Sertraline (an antidepressant) and tolterodine (Detrol, used for an overactive bladder) can affect each other in two ways when taken together. First, both can slightly affect the heart's electrical rhythm (called the QT interval), and using them together can add to that effect. Second, sertraline can slow down how your body breaks down tolterodine, so more of it may build up in your system.
This can mean stronger tolterodine side effects like dry mouth, constipation, or dizziness, and a small increase in heart rhythm risk. The good news is your care team can manage this by adjusting your dose and keeping an eye on you. Please don't stop or change either medicine on your own, just talk with your pharmacist or doctor.
Interaction: Additive QTc prolongation plus sertraline inhibition of CYP2D6, increasing tolterodine exposure. Tolterodine is metabolized by CYP2D6 to an active 5-hydroxymethyl metabolite; in CYP2D6-extensive metabolizers, inhibition raises parent-drug levels and antimuscarinic burden. Both agents carry QT-prolonging potential.
- Direction: Increased tolterodine (CYP2D6 substrate) exposure and additive QTc risk.
- Severity/Evidence: Major; probable. Onset unspecified.
- Management: Avoid concomitant use where possible. If combined, consider tolterodine dose reduction and monitor ECG/QTc, electrolytes (K+, Mg2+), and antimuscarinic adverse effects. If sertraline is discontinued, tolterodine dose may need to be increased.
What happens
Increased risk of QT interval prolongation and an increased CYP2D6 substrate exposure
Interaction Deep Dive
Sertraline acts as both a CYP2D6 inhibitor and a QT interval prolonging agent, so it should not be combined with medications that are QT prolonging substrates of CYP2D6. When taken alongside other agents that lengthen the QTc interval, the likelihood of QTc prolongation and/or ventricular arrhythmias rises. It may be necessary to lower the dose of the CYP2D6 substrate. On the other hand, if sertraline is stopped, the dosage of the CYP2D6 substrate may need to be raised1.
Why it happens (mechanism)
Additive QT interval prolongation; inhibition of CYP2D6-substrate metabolism by sertraline
How to manage this interaction
Your care team will weigh whether these two should be used together, and they have clear ways to manage it if they are:
- Your tolterodine dose may be adjusted and individualized by your prescriber, since sertraline can raise its levels.
- They may monitor you more closely, which can include checking your heart rhythm (an ECG) and watching for side effects like dry mouth, constipation, or dizziness.
- If sertraline is ever stopped, your tolterodine dose may need to be increased again.
Keep taking both as prescribed and ask your pharmacist or doctor before making any changes. Mention any fainting, palpitations, or irregular heartbeat right away.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
1 report — tap to read
a) Mean plasma levels of risperiDONE 4 to 8 mg/day (a substrate of CYP2D6) rose about 4-fold when it was given together with PARoxetine 20 mg/day 2.
Common questions
Can I take Sertraline and Tolterodine together?
Sertraline can raise tolterodine levels and add to heart-rhythm (QT) risk, so this combination is often avoided; if used together, your doctor may lower the tolterodine dose and monitor your heart. 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 Tolterodine 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 Tolterodine interaction managed?
Your care team will weigh whether these two should be used together, and they have clear ways to manage it if they are: Your tolterodine dose may be adjusted and individualized by your prescriber, since sertraline can raise its levels. They may monitor you more closely, which can include checking your heart rhythm (an ECG) and watching for side effects like dry mouth, constipation, or dizziness. I… Management is individual — always follow your own care team's guidance.
How strong is the evidence for this interaction?
The evidence is graded "probable". Good supporting evidence, though not definitively proven.
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 Tolterodine 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: PEXEVA(R) oral tablets, paroxetine mesylate oral tablets. Sebela Pharmaceuticals Inc (per FDA), Roswell, GA, 2023.
Keep reading about Sertraline
Keep reading about Tolterodine
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major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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