Acetaminophen And Codeine and Rifabutin: Interaction Details
AI-assisted, pharmacist-reviewed · AI content regenerated Jul 11, 2026 · Source data updated Jul 1, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Acetaminophen And Codeine
Rifabutin
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.
Here's what's going on. Codeine is a pain medicine that your body has to turn on before it works, partly using a liver pathway called CYP3A4. Rifabutin (Mycobutin) speeds that pathway up. When it does, more of your codeine gets pushed down a route that makes less of the active pain-relieving form (morphine). The result can be less pain relief, and if your body is used to the opioid, you might even feel early withdrawal symptoms like sweating, chills, or an upset stomach.
The good news is your care team can manage this by watching how well your pain is controlled and adjusting your dose if needed. Don't change anything on your own, just talk with your doctor or pharmacist.
Mechanism: Rifabutin induces CYP3A4, increasing shunting of codeine toward norcodeine and reducing CYP2D6-mediated conversion to morphine, the active analgesic metabolite. Codeine is a prodrug, so induction reduces active opioid exposure.
- Effect: Lower codeine/morphine exposure, reduced analgesia, possible precipitated withdrawal in opioid-dependent patients.
- Severity/Evidence: Major; theoretical. Onset unspecified.
- Management: Monitor for reduced efficacy and withdrawal signs; codeine dose may be increased and individualized. If rifabutin is discontinued, anticipate rising opioid levels, consider codeine dose reduction, and monitor for sedation and respiratory depression.
What happens
Reduced codeine and morphine exposure, reduced opioid efficacy and precipitation of opioid withdrawal
Interaction Deep Dive
When codeine is taken together with CYP3A4 inducers, codeine concentrations may fall while norcodeine concentrations rise, and CYP2D6-mediated metabolism may decline, lowering morphine levels. This can diminish therapeutic effect or trigger a withdrawal syndrome in patients who have become physically dependent. Should combined use be required, monitor patients carefully for reduced efficacy or indications of opioid withdrawal syndrome, and increase the codeine dose as needed. When a CYP3A4 inducer is being stopped, consider lowering the codeine dose and watch patients closely for signs of respiratory depression or sedation12.
Why it happens (mechanism)
Induction of CYP3A4-mediated codeine metabolism
How to manage this interaction
Keep taking both medications as prescribed unless your care team tells you otherwise. This interaction is manageable.
- Your team may monitor you more closely for whether your pain relief is working and for early signs of opioid withdrawal (chills, sweating, body aches, stomach upset).
- Your codeine dose may need to be adjusted and individualized by your care team to keep pain controlled.
- If the rifabutin is ever stopped, tell your team, since your codeine may then become stronger and the dose may need lowering.
Report worsening pain or withdrawal symptoms to your pharmacist or prescriber.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Acetaminophen And Codeine and Rifabutin together?
Rifabutin can make codeine work less well by speeding up its breakdown, so watch for weaker pain relief or withdrawal symptoms and let your care team adjust your dose if needed. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Acetaminophen And Codeine and Rifabutin 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 Rifabutin interaction managed?
Keep taking both medications as prescribed unless your care team tells you otherwise. This interaction is manageable. Your team may monitor you more closely for whether your pain relief is working and for early signs of opioid withdrawal (chills, sweating, body aches, stomach upset). Your codeine dose may need to be adjusted and individualized by your care team to keep pain controlled. If the rifa… 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 Rifabutin 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 Acetaminophen And Codeine
Keep reading about Rifabutin
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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