Codeine and Sertraline: 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 recordCodeine
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.
Codeine is a prodrug. Your body has to turn it into morphine (using an enzyme called CYP2D6) before it can relieve pain. Sertraline can block that enzyme, so you may make less morphine. That means codeine might not work as well for pain, and if you take it regularly your body could feel like it is going into withdrawal.
There is also a second concern. Both drugs raise a brain chemical called serotonin, so taking them together can, rarely, cause a reaction called serotonin syndrome (agitation, sweating, shivering, fast heartbeat, muscle twitching). This is mostly theoretical, but worth knowing. The good news: your care team can manage this by tailoring your dose and watching how you respond.
Direction: Sertraline is a moderate CYP2D6 inhibitor. Codeine is a prodrug requiring CYP2D6 for O-demethylation to morphine (active metabolite). Inhibition raises codeine exposure but reduces morphine formation, lowering analgesic efficacy and risking withdrawal in dependent patients.
- PD overlap: Both serotonergic, giving additive risk of serotonin syndrome.
- Evidence: Theoretical; severity major.
- Management: If combined, monitor for reduced analgesia/withdrawal; codeine dose may be individualized upward. On stopping sertraline, anticipate increased morphine formation and monitor for respiratory depression, reducing codeine as needed. Observe for serotonin syndrome, especially at initiation/titration; discontinue codeine if suspected.
What happens
Increased risk of serotonin syndrome, increased codeine exposure and reduced active metabolite (morphine) exposure
Interaction Deep Dive
When codeine is taken together with a CYP2D6 inhibitor, the plasma levels of morphine (the active metabolite formed from codeine) may fall, which could diminish the drug's effectiveness or trigger a withdrawal syndrome in patients who have become physically dependent. Should combined use be required, watch for signs of withdrawal and think about raising the codeine dose. When the CYP2D6 inhibitor is later stopped, consider lowering the codeine dose and observe for respiratory depression. Serotonin syndrome has also occurred when opioids are used alongside serotonergic agents. If this combination is necessary, monitor the patient closely, especially when starting therapy and when doses are being changed. Codeine should be stopped if serotonin syndrome is suspected12.
Why it happens (mechanism)
Additive serotonergic effects; inhibition of CYP2D6-mediated codeine metabolism
How to manage this interaction
Keep taking both exactly as prescribed unless your prescriber tells you otherwise. Your care team can manage this combination safely.
- Your codeine dose may need to be adjusted and individualized by your care team, and they may monitor you more closely.
- Watch for signs codeine isn't working well, or withdrawal-type symptoms if you take it regularly.
- If sertraline is later stopped, codeine may become stronger, so your team may lower the dose and watch your breathing.
- Get urgent help for serotonin syndrome signs: agitation, fast heartbeat, sweating, shivering, muscle twitching, or confusion.
Raise any of these with your pharmacist or prescriber.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Codeine and Sertraline together?
Sertraline can blunt codeine's pain relief (codeine needs CYP2D6 to become morphine) and, rarely, add to serotonin syndrome risk; your care team can manage this by adjusting the codeine dose and monitoring you, so don't change anything on your own. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Codeine and Sertraline 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 Codeine and Sertraline interaction managed?
Keep taking both exactly as prescribed unless your prescriber tells you otherwise. Your care team can manage this combination safely. Your codeine dose may need to be adjusted and individualized by your care team, and they may monitor you more closely. Watch for signs codeine isn't working well, or withdrawal-type symptoms if you take it regularly. If sertraline is later stopped, codeine may becom… 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 Codeine or Sertraline 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: Codeine sulfate oral solution, codeine sulfate oral solution. Hikma Pharmaceuticals USA Inc(per FDA), Berkeley Heights, NJ, 2023. DailyMed
- Product Information: Codeine sulfate oral tablets, codeine sulfate oral tablets. Hikma Pharmaceuticals USA Inc. (per FDA), Berkeley Heights, NJ, 2023. DailyMed
Keep reading about Sertraline
Keep reading about Codeine
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major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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