Citalopram and Amitriptyline: 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
Amitriptyline
Citalopram
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.
Amitriptyline (Elavil) and citalopram (Celexa) can add up in two ways when taken together. First, both can affect your heart's rhythm (something called QT prolongation), which in rare cases can cause dangerous heartbeats. Second, both raise serotonin, a brain chemical, so together they can rarely trigger serotonin syndrome (symptoms like agitation, shakiness, sweating, a fast heartbeat, or fever).
Citalopram can also slow down how your body breaks amitriptyline down, so amitriptyline may build up. This concern is mostly theoretical, and your care team can manage it well by tailoring your doses and keeping an eye on you. Please don't stop either drug on your own. Just talk with your doctor or pharmacist.
Effect: Additive QT prolongation and additive serotonergic effects, raising risk of serious cardiovascular events and serotonin syndrome. Combination is generally not recommended.
- Mechanism: Additive QTc prolongation plus additive serotonin activity. Citalopram also inhibits CYP2D6, reducing amitriptyline clearance and raising its exposure (neither is a prodrug requiring activation here).
- Evidence: Theoretical; severity major. Onset unspecified.
- Management: If co-prescribed, obtain baseline/periodic ECG, do not exceed citalopram 40 mg/day, discontinue citalopram if persistent QTc >500 ms or serotonin syndrome. Monitor amitriptyline levels; lower doses of either agent may be required. Provide supportive care for serotonin syndrome.
What happens
An increased risk of QT interval prolongation and an increased risk of serotonin syndrome
Interaction Deep Dive
Combining amitriptyline with citalopram is advised against because of the possibility of additive QT interval prolongation together with a heightened risk of serious cardiovascular events and serotonin syndrome. Should the combination be necessary, watch for ECG alterations and for signs of serotonin syndrome. Citalopram should not be given at doses above 40 mg/day, and it should be stopped in patients whose QTc readings remain above 500 milliseconds. If features of serotonin syndrome develop, begin supportive therapy2. Furthermore, care is warranted when amitriptyline, which is a CYP2D6 substrate, is combined with a CYP2D6 inhibitor like citalopram, since reduced doses of amitriptyline and/or citalopram may be needed. Monitoring amitriptyline concentrations is preferable any time a CYP2D6 inhibitor is used at the same time 1.
Why it happens (mechanism)
Additive QT interval prolongation; additive serotonergic effects
How to manage this interaction
The good news: your care team can manage this by tailoring doses and monitoring you. Keep taking both exactly as prescribed unless your prescriber tells you otherwise.
- Your team may check an ECG to watch your heart rhythm (QT interval).
- Citalopram is typically kept at or below 40 mg per day.
- Your amitriptyline dose (and sometimes citalopram) may be adjusted and individualized, and your team may check amitriptyline blood levels.
- Learn the signs of serotonin syndrome (agitation, tremor, sweating, racing heart, fever) and get urgent care if they occur.
Ask your pharmacist or doctor before making any change.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Citalopram and Amitriptyline together?
Combining amitriptyline and citalopram adds to the risk of heart-rhythm changes and serotonin syndrome, and citalopram can raise amitriptyline levels; it's generally avoided, but if you need both, your care team can manage it with dose adjustments and monitoring. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Citalopram and Amitriptyline 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 Citalopram and Amitriptyline interaction managed?
The good news: your care team can manage this by tailoring doses and monitoring you. Keep taking both exactly as prescribed unless your prescriber tells you otherwise. Your team may check an ECG to watch your heart rhythm (QT interval). Citalopram is typically kept at or below 40 mg per day. Your amitriptyline dose (and sometimes citalopram) may be adjusted and individualized, and your team may ch… 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
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Questions for your pharmacist
- Does my dose of Citalopram or Amitriptyline 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)
Keep reading about Amitriptyline
Keep reading about Citalopram
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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