Dolasetron and Acetaminophen And Codeine: Interaction Details
AI-assisted, pharmacist-reviewed · AI content regenerated Jul 11, 2026 · Source data updated Jun 30, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Dolasetron
Acetaminophen And Codeine
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.
You've been given dolasetron (an anti-nausea medicine) along with acetaminophen and codeine (a pain reliever). Both can gently raise a brain chemical called serotonin. When two medicines do this at the same time, there's a small chance of a reaction called serotonin syndrome.
Signs to watch for include feeling agitated or restless, a fast heartbeat, sweating, shaking, muscle twitching, or fever. This is considered a theoretical concern, meaning it's not common, but it's worth knowing. The good news is your care team can manage this by keeping an eye on you, especially when you first start or change doses. If you ever feel these symptoms, reach out to your pharmacist or doctor right away.
Effect: Additive serotonergic activity may increase the risk of serotonin syndrome when dolasetron (a 5-HT3 antagonist) is combined with codeine (an opioid with weak serotonergic properties).
- Direction: Additive pharmacodynamic effect; not a metabolic/PK interaction.
- Evidence: Theoretical; severity rated major.
- Onset: Unspecified; risk highest at initiation and dose changes.
- Management: Concomitant use is acceptable if clinically needed. Monitor for autonomic instability, neuromuscular abnormalities (clonus, hyperreflexia, rigidity), and altered mental status. Discontinue codeine if serotonin syndrome is suspected.
What happens
Increased risk of serotonin syndrome
Interaction Deep Dive
Concomitant use of opioids, such as codeine, with serotonergic drugs has resulted in serotonin syndrome. If concomitant use is needed, carefully observe the patient, particularly during treatment initiation and dose adjustments. Discontinue codeine if serotonin syndrome is suspected123.
Why it happens (mechanism)
Additive serotonergic effects
How to manage this interaction
If both medicines are prescribed together, that can be appropriate. Here's how this is typically handled:
- Keep taking both as prescribed unless your care team tells you otherwise.
- Your team may watch you more closely, especially when you first start or when a dose is adjusted.
- Watch for warning signs: agitation, confusion, fast heartbeat, sweating, tremor, muscle twitching, or fever.
Contact your pharmacist or prescriber promptly if these symptoms appear. Ask them any questions about combining these two medicines, and don't stop either one on your own.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
1 report — tap to read
Common questions
Can I take Dolasetron and Acetaminophen And Codeine together?
Combining dolasetron with codeine carries a small, mainly theoretical risk of serotonin syndrome from added serotonin effects. Keep taking both as prescribed, watch for symptoms like agitation, fast heartbeat, sweating, tremor, or fever, and contact your care team if they occur. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Dolasetron and Acetaminophen And Codeine 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 Dolasetron and Acetaminophen And Codeine interaction managed?
If both medicines are prescribed together, that can be appropriate. Here's how this is typically handled: Keep taking both as prescribed unless your care team tells you otherwise. Your team may watch you more closely, especially when you first start or when a dose is adjusted. Watch for warning signs: agitation, confusion, fast heartbeat, sweating, tremor, muscle twitching, or fever. Contact your… 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.
Questions for your pharmacist
- Does my dose of Dolasetron or Acetaminophen And Codeine 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 (3)
- Product Information: Codeine sulfate oral tablets, codeine sulfate oral tablets. West-Ward Pharmaceuticals Corp (per DailyMed), Eatontown, NJ, 2016. DailyMed
- 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 Dolasetron
Keep reading about Acetaminophen And Codeine
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