Acetaminophen And Codeine and Kava: 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
Kava
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.
Both of these can make you sleepy, and together the effect can add up. Codeine is an opioid pain reliever (combined here with acetaminophen, the medicine in Tylenol), and kava is an herbal supplement that has a calming, sedating effect. When you take them together, you may feel more drowsy, foggy, or slowed down than you would from either one alone.
This concern is based on theory rather than strong studies, so it does not mean something bad will definitely happen. Still, it is worth taking seriously. Please talk with your pharmacist or doctor before combining them, and be careful about driving until you know how you feel.
Effect: Additive CNS depression when kava is combined with the codeine component of this product.
- Mechanism: Pharmacodynamic additive sedation; both agents depress the CNS. Not a pharmacokinetic/enzyme interaction (codeine is a prodrug activated by CYP2D6, but that pathway is not involved here).
- Direction/magnitude: Enhanced sedation, drowsiness, slowed reflexes; theoretically hypotension or profound sedation.
- Onset: Unspecified. Evidence: Theoretical.
- Management: Avoid concomitant use. If used, monitor for sedation and psychomotor impairment; counsel against driving or operating machinery. Dosing may be individualized by the care team.
What happens
Increased central nervous system depression
Interaction Deep Dive
In theory, kava could produce additive sedative effects when taken together with any drug that has sedating properties, opioid analgesics included 1. Concurrent use of meperidine and kava may lead to hypotension, deep sedation, or coma. It is advised that lowered doses of meperidine be given 2.
Why it happens (mechanism)
Additive central nervous system depression
How to manage this interaction
Keep taking your prescribed medicine as directed, and raise the kava question with your pharmacist or prescriber before combining them.
- The usual advice is to avoid using kava together with opioid pain medicines like codeine.
- If your care team agrees you may use both, they will watch you closely for sedation, drowsiness, or slowed reflexes.
- Avoid driving or operating heavy machinery until you know how the combination affects you.
- Your dose may need to be adjusted and individualized by your care team.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Acetaminophen And Codeine and Kava together?
Kava and codeine (with acetaminophen) can add up to make you very drowsy, so it is best to avoid the combination; check with your pharmacist or doctor, and do not drive until you know how you feel. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Acetaminophen And Codeine and Kava interaction?
It is rated moderate. Can be significant — usually manageable with 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 Kava interaction managed?
Keep taking your prescribed medicine as directed, and raise the kava question with your pharmacist or prescriber before combining them. The usual advice is to avoid using kava together with opioid pain medicines like codeine. If your care team agrees you may use both, they will watch you closely for sedation, drowsiness, or slowed reflexes. Avoid driving or operating heavy machinery until you know… 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 Kava 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 anything you'd monitor while I'm on both?
References (2)
- Brinker FBrinker F: Herb Contraindications and Drug Interactions, 2nd. Eclectic Medical Publications, Sandy, OR, 1998.
- Product Information: Demerol(R), meperidine hydrochloride. Sanofi-Synthelabo Inc. New York, NY, 2002. DailyMed
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