Acetaminophen And Codeine and Periciazine: 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
Acetaminophen And Codeine
Periciazine
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.
These two medicines can make each other stronger in a way that slows you down. Your acetaminophen with codeine contains an opioid (codeine), which can make you drowsy and slow your breathing. Periciazine is an antipsychotic that also causes sedation. Taken together, they can add up, so you may feel very sleepy, dizzy, confused, or short of breath.
This is a caution based more on how these drugs work than on lots of real-world reports, but it is worth taking seriously. The good news is your care team can manage this safely, often by adjusting the dose and watching you more closely. Please don't stop either one on your own. Just talk with your pharmacist or doctor.
Effect: Additive CNS depression from combining codeine (opioid) plus periciazine (phenothiazine antipsychotic). Acetaminophen is not the concern here.
- Mechanism: Pharmacodynamic, additive CNS and respiratory depression, sedation, hypotension. Not a pharmacokinetic/prodrug issue for this pairing.
- Direction/magnitude: Enhanced depressant effect of both agents; magnitude not quantified.
- Onset: Unspecified. Evidence: Theoretical, but rated major.
- Management: If coadministered, consider reducing the CNS depressant (opioid) dose by at least 50% while periciazine is gradually titrated. Monitor sedation, respiratory rate, and blood pressure.
What happens
Risk of enhanced CNS depression
Interaction Deep Dive
When periciazine is taken together with other phenothiazine derivatives or CNS depressants, the CNS depressant actions of both drugs may be intensified. Should these agents be given at the same time, lower the dose of the phenothiazine derivative or CNS depressant by no less than 50% during the gradual introduction of periciazine12.
Why it happens (mechanism)
Additive CNS depression
How to manage this interaction
The main thing is watching for excess sedation. Your care team can keep this combination safe by tailoring your doses and monitoring you.
- Keep taking both exactly as prescribed unless your prescriber tells you otherwise.
- Your team may lower the dose of one medicine (often by at least half) and start periciazine slowly.
- They may check you more closely for drowsiness, dizziness, confusion, or slowed breathing.
- Avoid alcohol and other sedating medicines unless cleared by your care team.
- Ask your pharmacist or doctor before making any change, and get help right away for very slow or shallow breathing.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Acetaminophen And Codeine and Periciazine together?
Combining codeine (in your acetaminophen/codeine) with periciazine can add up to stronger drowsiness and slowed breathing, so your care team may lower a dose and monitor you more closely. Keep taking both as prescribed and check with your pharmacist or doctor before changing anything. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Acetaminophen And Codeine and Periciazine 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 Acetaminophen And Codeine and Periciazine interaction managed?
The main thing is watching for excess sedation. Your care team can keep this combination safe by tailoring your doses and monitoring you. Keep taking both exactly as prescribed unless your prescriber tells you otherwise. Your team may lower the dose of one medicine (often by at least half) and start periciazine slowly. They may check you more closely for drowsiness, dizziness, confusion, or slowed… 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 Acetaminophen And Codeine or Periciazine 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: Pericyazine oral tablets, pericyzaine oral tablets. Winthrop Pharmaceuticals UK Ltd (per emc+), Guildford, Surrey, United Kingdom, 2015.
- Product Information: NEULEPTIL oral capsules, drops, periciazine oral capsules, drops. ERFA Canada Inc. (per Health Canada), Montreal, QC, Canada, 2012.
Keep reading about Acetaminophen And Codeine
Keep reading about Periciazine
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