Acetaminophen And Codeine and Ethinyl Estradiol: 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
Ethinyl Estradiol
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.
You're taking acetaminophen with codeine (a pain reliever) along with a birth control pill that contains ethinyl estradiol. These two can nudge each other's levels. The acetaminophen can slow down how your body clears the estrogen, so a bit more estrogen may stay in your blood. At the same time, the birth control pill can lower your acetaminophen levels a little, which might make the pain relief slightly weaker.
This is based on theoretical lab reasoning, not strong real-world proof, so it's usually a mild concern. Keep taking both as prescribed, and just mention that you use them together to your pharmacist or doctor so they can keep an eye on things.
Effect: Increased ethinyl estradiol exposure and decreased acetaminophen exposure.
- Mechanism: Acetaminophen may inhibit conjugation (glucuronidation/sulfation) of ethinyl estradiol, raising its plasma levels. COCs conversely enhance acetaminophen clearance, lowering acetaminophen concentrations. (Codeine is a prodrug activated via CYP2D6, but it is not implicated in this pathway.)
- Direction/magnitude: Modest bidirectional PK shift; magnitude not well quantified.
- Onset: Unspecified.
- Evidence: Theoretical.
- Management: No routine adjustment required; be aware of possible reduced analgesia and slightly higher estrogen exposure. Dose may be individualized and patients monitored clinically if warranted.
What happens
Increased ethinyl estradiol exposure and reduced acetaminophen exposure
Interaction Deep Dive
Concomitant use of acetaminophen and an oral combination contraceptive that contains ethinyl estradiol and norethindrone may cause elevated plasma concentrations of ethinyl estradiol possibly by inhibition of conjugation. Also, COCs have been shown to decrease plasma concentrations of acetaminophen1.
Why it happens (mechanism)
Inhibition of conjugation; unknown
How to manage this interaction
This is a low-level, mostly theoretical interaction, so there is usually nothing dramatic to do. Here is the practical picture:
- Keep taking both as prescribed unless your care team tells you otherwise.
- Watch whether your pain relief feels a bit weaker than expected, since the birth control pill can lower acetaminophen levels.
- Your team can individualize your dosing and monitor you more closely if needed.
Let your pharmacist or prescriber know you use both together. Bring up any change in how well your pain medicine works or any new estrogen-related symptoms.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Acetaminophen And Codeine and Ethinyl Estradiol together?
Acetaminophen may raise your estrogen levels slightly while the birth control pill may make your acetaminophen work a bit less. It's a mild, theoretical interaction, so keep taking both as prescribed and tell your pharmacist or doctor. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Acetaminophen And Codeine and Ethinyl Estradiol 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 Ethinyl Estradiol interaction managed?
This is a low-level, mostly theoretical interaction, so there is usually nothing dramatic to do. Here is the practical picture: Keep taking both as prescribed unless your care team tells you otherwise. Watch whether your pain relief feels a bit weaker than expected, since the birth control pill can lower acetaminophen levels. Your team can individualize your dosing and monitor you more closely if… 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 Ethinyl Estradiol 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 (1)
- Product Information: LOESTRIN(R) 24 Fe oral tablets, norethindrone acetate ethinyl estradiol oral tablets, ferrous fumarate oral tablets. Teva Pharmaceuticals USA Inc (per FDA), Parsippany, NJ, 2023. DailyMed
Keep reading about Acetaminophen And Codeine
Keep reading about Ethinyl Estradiol
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.
Check another combination
Our instant two-drug interaction checker is almost here.
Still have questions about this combination?
Every question gets a real answer from a licensed pharmacist — free, and usually within a day.
Ask the pharmacist