Acetaminophen And Codeine and Stramonium: 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
Stramonium
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.
Let's talk about taking codeine (the pain reliever paired with acetaminophen in medicines like Tylenol with Codeine) together with stramonium, which is a plant-based anticholinergic remedy. Both of these can slow down your gut and make it harder to empty your bladder.
When you use them together, that slowing effect can add up. This may lead to severe constipation or trouble urinating, and in rare cases the bowel can nearly stop moving (called a paralytic ileus). I'll be honest, this concern is mostly based on how these drugs work rather than lots of real-world reports. Still, watch for belly pain, bloating, no bowel movements, or trouble peeing, and let your care team know. They can help manage this easily.
Effect: Additive reduction in GI motility and urinary function when codeine (an opioid) is combined with stramonium (a belladonna-alkaloid anticholinergic containing atropine/scopolamine-type compounds).
Mechanism: Pharmacodynamic additivity. Opioid-induced slowing of gut transit plus antimuscarinic inhibition of smooth muscle motility and bladder emptying increases risk of severe constipation, urinary retention, and potentially paralytic ileus.
- Direction: Increased adverse anticholinergic/constipating effect.
- Evidence: Theoretical; onset unspecified.
- Severity: Major.
- Monitoring: Bowel function, abdominal distension, bowel sounds, and urinary retention. Consider prophylactic bowel regimen; adjust or individualize therapy per response.
What happens
An increased risk of paralytic ileus
Interaction Deep Dive
When codeine is taken together with anticholinergic agents, there may be a heightened likelihood of urinary retention and/or serious constipation, potentially progressing to paralytic ileus. In patients receiving codeine alongside anticholinergic drugs, watch for indications of urinary retention or diminished gastric motility1.
Why it happens (mechanism)
Additive effects on gastric motility
How to manage this interaction
The good news is your care team can manage this by keeping an eye on how your gut and bladder are working, and tailoring things to you.
- Keep taking both as prescribed unless your doctor or pharmacist tells you otherwise.
- Watch for severe constipation, bloating, belly pain, no bowel movements, or trouble urinating, and report these promptly.
- Your team may recommend closer monitoring, a bowel regimen (like fluids, fiber, or a stool softener), or may adjust and individualize your treatment.
Ask your pharmacist before combining codeine products with any anticholinergic herbal or plant-based product like stramonium.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Acetaminophen And Codeine and Stramonium together?
Combining codeine with stramonium can add up to slow your gut and bladder, raising the risk of severe constipation, urinary retention, and rarely a paralytic ileus. Keep taking both as prescribed, watch for these symptoms, and check with your pharmacist or doctor. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Acetaminophen And Codeine and Stramonium 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 Stramonium interaction managed?
The good news is your care team can manage this by keeping an eye on how your gut and bladder are working, and tailoring things to you. Keep taking both as prescribed unless your doctor or pharmacist tells you otherwise. Watch for severe constipation, bloating, belly pain, no bowel movements, or trouble urinating, and report these promptly. Your team may recommend closer monitoring, a bowel regime… 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 Stramonium 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 (1)
- Product Information: CARISOPRODOL, ASPIRIN, CODEINE PHOSPHATE oral tablets, carisoprodol, aspirin, codeine phosphate oral tablets. Ingenus Pharmaceuticals LLC (per DailyMed), Orlando, FL, 2021. DailyMed
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