Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
ADVIL PM vs ACETAMINOPHEN AND CODEINE PHOSPHATE
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that inhibits cyclooxygenase (COX) enzymes, reducing prostaglandin synthesis. Diphenhydramine is a first-generation antihistamine that antagonizes histamine H1 receptors, causing sedation.
Acetaminophen: centrally acting analgesic and antipyretic, possibly via inhibition of cyclooxygenase (COX) and modulation of cannabinoid receptors. Codeine: prodrug converted to morphine; mu-opioid receptor agonist.
Temporary relief of occasional sleeplessness associated with minor aches and pains
Mild to moderate pain,Pain accompanied by fever
Two caplets (ibuprofen 200 mg, diphenhydramine citrate 38 mg) orally at bedtime as needed for insomnia. Maximum: 2 caplets in 24 hours.
One or two tablets (acetaminophen 300 mg/codeine 30 mg per tablet) orally every 4-6 hours as needed for pain; maximum 12 tablets daily.
Ibuprofen: 2-4 hours (terminal); clinical context: steady state achieved in 1 day, not affected by renal impairment. Diphenhydramine: 4-8 hours (terminal); clinical context: prolonged in hepatic impairment.
Acetaminophen: 2–3 hours (prolonged in hepatic impairment). Codeine: 2.5–3.5 hours; metabolites: morphine 1.5–2.5 hours, codeine-6-glucuronide 3–4 hours. Clinical context: dosing interval every 4–6 hours.
Ibuprofen is primarily metabolized via hepatic oxidation by CYP2C9. Diphenhydramine is metabolized via hepatic N-demethylation and oxidation, primarily by CYP2D6.
Acetaminophen: primarily glucuronidation and sulfation in liver; minor CYP450 (CYP2E1) to toxic NAPQI. Codeine: CYP2D6 to morphine; CYP3A4 to norcodeine; glucuronidation.
Ibuprofen: Renal (90% as metabolites and conjugates, <10% unchanged); Diphenhydramine: Renal (primarily as metabolites, ~1% unchanged). Fecal excretion is negligible for both.
Acetaminophen: renal elimination of conjugated metabolites (glucuronide 60%, sulfate 30%, cysteine/mercapturate <5%), less than 5% unchanged. Codeine: renal elimination of codeine (5–15%), morphine (5–10%), norcodeine (10–20%), and conjugates; 90% excreted in urine within 24 hours.
Ibuprofen: >99% bound to albumin; Diphenhydramine: 78-85% bound to albumin.
Acetaminophen: 10–25% (albumin). Codeine: 7–25% (primarily albumin).
Ibuprofen: 0.1-0.2 L/kg; small Vd consistent with high protein binding. Diphenhydramine: 4.5-8.5 L/kg; large Vd indicating extensive tissue distribution.
Acetaminophen: 0.9 L/kg. Codeine: 3–6 L/kg (extensive tissue distribution).
Ibuprofen: 80-100% (oral); Diphenhydramine: 50-70% (oral) due to first-pass metabolism.
Oral: acetaminophen 88% (variable first-pass); codeine 50–60% (first-pass metabolism to morphine, norcodeine, and conjugates).
Avoid use in GFR <30 m L/min. For GFR 30-59 m L/min, limit to single dose and avoid chronic use. No adjustment needed for GFR ≥60 m L/min.
GFR 30-50 m L/min: administer every 6 hours; GFR 10-29 m L/min: administer every 8 hours; GFR <10 m L/min: administer every 12 hours; hemodialysis: not recommended.
Contraindicated in Child-Pugh Class C. In Child-Pugh Class B, reduce dose by 50% (max 1 caplet) and monitor for toxicity. No adjustment for Child-Pugh Class A.
Child-Pugh A: no adjustment; Child-Pugh B: reduce dose by 50% and extend interval to every 8 hours; Child-Pugh C: contraindicated.
Not recommended for children under 12 years. For age ≥12 years, same adult dose: 2 caplets at bedtime.
For children ≥12 years: acetaminophen 10-15 mg/kg/dose and codeine 0.5-1 mg/kg/dose orally every 4-6 hours; maximum acetaminophen 75 mg/kg/day, codeine 6 mg/kg/day. For children <12 years: not recommended due to codeine safety concerns.
Start with lowest effective dose (1 caplet) at bedtime to minimize anticholinergic and GI adverse effects. Avoid in elderly with cognitive impairment or high fall risk.
Start with lowest effective dose; acetaminophen component maximum 3 g/day; consider reduced codeine dose (e.g., 15 mg) due to increased sensitivity and risk of respiratory depression; extend dosing interval to every 6-8 hours.
NSAIDs cause an increased risk of serious cardiovascular thrombotic events, including myocardial infarction and stroke, which can be fatal. This risk may occur early in treatment and may increase with duration of use. NSAIDs are contraindicated in the setting of coronary artery bypass graft (CABG) surgery.
Risk of medication errors: confusion between milligram and milliliter doses, and between codeine and acetaminophen components. Contraindicated for postoperative pain management in children following tonsillectomy/adenoidectomy due to risk of respiratory depression and death.
Cardiovascular thrombotic events,Gastrointestinal bleeding, ulceration, and perforation,Renal toxicity,Sedation and impaired cognitive function,Anticholinergic effects,Avoid use with other NSAIDs or antihistamines,Use caution in elderly, renal impairment, hepatic impairment, and pregnancy
Hepatotoxicity (acetaminophen overdose); respiratory depression; drug dependence; ultra-rapid metabolizers of codeine (CYP2D6) leading to morphine toxicity; concomitant CNS depressants; use in pediatric patients; avoid alcohol.
Hypersensitivity to ibuprofen, diphenhydramine, or any component of the formulation,History of asthma, urticaria, or allergic-type reactions after taking aspirin or other NSAIDs,Perioperative pain in the setting of coronary artery bypass graft (CABG) surgery,Neonates and premature infants (due to diphenhydramine),Concurrent use with other diphenhydramine products or sedatives
Hypersensitivity to acetaminophen or codeine; severe respiratory depression; acute or severe asthma; paralytic ileus; post-operative pain management in children after tonsillectomy/adenoidectomy; breastfeeding (in ultra-rapid metabolizers); concomitant MAOIs.
Take with food or milk to reduce GI upset. Avoid alcohol and grapefruit juice. Caffeine may enhance CNS stimulation and should be limited.
Avoid alcohol; high-fat meals may delay absorption but not clinically significant.
Pregnancy Category C/D (after 30 weeks). First trimester: Potential risk of miscarriage and cardiac defects (limited data with NSAIDs). Second trimester: Avoid unless clearly needed; possible oligohydramnios, premature closure of ductus arteriosus, and fetal renal impairment. Third trimester: Contraindicated after 30 weeks due to risk of premature ductus arteriosus closure and persistent pulmonary hypertension.
Acetaminophen is considered low risk in all trimesters at therapeutic doses; chronic high doses may be associated with adverse outcomes. Codeine is associated with risk of respiratory depression and neonatal withdrawal if used near term; may cause neural tube defects and other malformations with first-trimester exposure, but data are conflicting. Use lowest effective dose for shortest duration.
Diphenhydramine and ibuprofen are excreted into breast milk. M/P ratio not established. Both drugs are considered compatible with breastfeeding in low doses, but theoretical risk of infant sedation (diphenhydramine) and gastrointestinal effects (ibuprofen). Max daily dose for mother should not exceed recommended limits. Monitor infant for drowsiness and poor feeding.
Acetaminophen is excreted into breast milk in low amounts (M/P ratio ~0.91-1.42) and is considered compatible with breastfeeding. Codeine is also excreted in breast milk; risk of infant opioid toxicity depends on maternal CYP2D6 phenotype. Ultra-rapid metabolizers may produce higher morphine levels. Use with caution, avoid in known CYP2D6 ultra-rapid metabolizers, and monitor infant for sedation and respiratory depression.
No specific dose adjustment recommended for ibuprofen or diphenhydramine in pregnancy. However, due to altered pharmacokinetics (increased volume of distribution, renal clearance), standard doses may be less effective. Avoid use if possible, especially after 30 weeks. Use lowest effective dose for shortest duration.
No routine dose adjustment needed for acetaminophen. Codeine pharmacokinetics are altered in pregnancy: increased clearance and volume of distribution may require dose adjustment; however, due to variability in CYP2D6 metabolism, individualize dosing and monitor for efficacy and toxicity. Avoid codeine in pregnancy unless alternative analgesics are ineffective.
Advil PM combines ibuprofen (NSAID) and diphenhydramine (antihistamine). Avoid concomitant use with other NSAIDs or CNS depressants (including alcohol). Use lowest effective dose for shortest duration. Contraindicated in severe hepatic/renal impairment, active GI bleeding, or during third trimester of pregnancy. May cause morning drowsiness due to antihistamine.
For acute pain, limit codeine to 3 days; avoid in children under 12 due to CYP2D6 ultra-rapid metabolizer risk of fatal respiratory depression; monitor for constipation; assess liver function for acetaminophen hepatotoxicity; use with caution in renal impairment.
Take only one tablet before bedtime; do not exceed recommended dose.,Avoid alcohol and other sedatives while using this medication.,Do not use for more than 10 days for pain or 3 days for fever unless directed by a doctor.,May cause drowsiness; avoid driving or operating machinery until you know how the drug affects you.,Not for use in children under 12 years of age or during pregnancy/breastfeeding without consulting a healthcare provider.,Report signs of stomach bleeding (e.g., black/tarry stools, vomiting blood) or allergic reactions (e.g., facial swelling, difficulty breathing).
Take exactly as prescribed; do not exceed 4000 mg acetaminophen per day.,Avoid alcohol while taking this medication.,Do not use with other acetaminophen-containing products.,May cause dizziness or drowsiness; avoid driving until you know how you react.,Common side effects include constipation, nausea, and drowsiness.,Seek emergency if signs of allergic reaction or difficulty breathing occur.
No interactions on record
"Pirenzepine, a selective M1 muscarinic antagonist, reduces gastrointestinal motility and secretions, while codeine, an opioid agonist, also decreases gastrointestinal motility via mu-opioid receptors. Concurrent use leads to additive anticholinergic and opioid effects, resulting in enhanced risk of severe constipation, paralytic ileus, and central nervous system depression. Clinically, patients may experience exacerbated sedation, respiratory depression, and urinary retention."
"Ropinirole, a non-ergoline dopamine agonist used in Parkinson's disease and restless legs syndrome, may reduce the analgesic efficacy of codeine. This is likely due to pharmacodynamic antagonism at central dopamine and opioid receptors, as well as potential pharmacokinetic interactions that decrease the conversion of codeine to its active metabolite morphine via CYP2D6 inhibition by ropinirole. The resultant blunted opioid response can lead to inadequate pain control, necessitating dose adjustment or alternative therapy."
"Vemurafenib induces CYP3A4, significantly reducing the plasma concentrations of codeine, which is metabolized via CYP3A4 to its active metabolite morphine. This may diminish codeine's analgesic efficacy, potentially leading to inadequate pain control. Additionally, reduced formation of morphine may lower the risk of opioid-related adverse effects."
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about ADVIL PM vs ACETAMINOPHEN AND CODEINE PHOSPHATE, answered by our medical review team.
ADVIL PM is a NSAID/Sedative Combination that works by Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that inhibits cyclooxygenase (COX) enzymes, reducing prostaglandin synthesis. Diphenhydramine is a first-generation antihistamine that antagonizes histamine H1 receptors, causing sedation.. ACETAMINOPHEN AND CODEINE PHOSPHATE is a Opioid Agonist that works by Acetaminophen: centrally acting analgesic and antipyretic, possibly via inhibition of cyclooxygenase (COX) and modulation of cannabinoid receptors. Codeine: prodrug converted to morphine; mu-opioid receptor agonist.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between ADVIL PM and ACETAMINOPHEN AND CODEINE PHOSPHATE depend on the specific clinical indication. These are agents from distinct pharmacological classes and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of ADVIL PM is: Two caplets (ibuprofen 200 mg, diphenhydramine citrate 38 mg) orally at bedtime as needed for insomnia. Maximum: 2 caplets in 24 hours.. The standard adult dose of ACETAMINOPHEN AND CODEINE PHOSPHATE is: One or two tablets (acetaminophen 300 mg/codeine 30 mg per tablet) orally every 4-6 hours as needed for pain; maximum 12 tablets daily.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between ADVIL PM and ACETAMINOPHEN AND CODEINE PHOSPHATE in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. ADVIL PM is classified as Category C. Pregnancy Category C/D (after 30 weeks). First trimester: Potential risk of miscarriage and cardiac defects (limited data with NSAIDs). Second trimester: Avoid unless clearly neede. ACETAMINOPHEN AND CODEINE PHOSPHATE is classified as Category D/X. Acetaminophen is considered low risk in all trimesters at therapeutic doses; chronic high doses may be associated with adverse outcomes. Codeine is associated with risk of respirat. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.