Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
ACETAMINOPHEN, ASPIRIN, AND CODEINE PHOSPHATE vs ACTIFED W/ CODEINE
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: June 2026 · OpiCalc Medical Review Team
Acetaminophen: cyclooxygenase (COX) inhibitor, primarily central, analgesic and antipyretic. Aspirin: irreversible COX-1 and COX-2 inhibitor, analgesic, anti-inflammatory, antipyretic, antiplatelet. Codeine: prodrug converted to morphine; mu-opioid receptor agonist.
Codeine is a prodrug that is metabolized to morphine, which acts as a mu-opioid receptor agonist; triprolidine is an H1 receptor antagonist. The combination produces antitussive and antihistamine effects.
Mild to moderate pain,Fever (acetaminophen and aspirin),Inflammatory conditions (aspirin)
Symptomatic relief of cough and upper respiratory symptoms associated with allergy or cold
1-2 tablets (each containing acetaminophen 300 mg, aspirin 300 mg, codeine phosphate 30 mg) orally every 4-6 hours as needed for pain; maximum 8 tablets/day.
Adults: 10 m L orally every 4-6 hours as needed, not to exceed 4 doses in 24 hours. Each 10 m L contains 10 mg codeine, 4 mg triprolidine, 60 mg pseudoephedrine.
Acetaminophen: 2-3 hours (terminal). Aspirin: 15-30 minutes (parent drug); salicylate: 2-3 hours at low doses, 15-30 hours at high doses due to saturable metabolism. Codeine: 2.5-4 hours. Clinical context: Prolonged half-life of salicylate at high doses increases risk of toxicity; hepatic impairment prolongs acetaminophen and codeine half-lives.
Codeine: 2.5-4 hours; pseudoephedrine: 5-8 hours; triprolidine: 3-6 hours. Context: Codeine half-life prolonged in hepatic impairment and CYP2D6 poor metabolizers; pseudoephedrine half-life increased with alkaline urine.
Acetaminophen: hepatic via CYP2E1, CYP1A2, CYP3A4; glucuronidation and sulfation; NAPQI formation. Aspirin: hepatic hydrolysis to salicylate; conjugation with glycine and glucuronic acid. Codeine: hepatic via CYP2D6 to morphine (active); also via CYP3A4 to norcodeine.
Codeine is metabolized primarily via glucuronidation and O-demethylation to morphine by CYP2D6, and N-demethylation to norcodeine by CYP3A4. Triprolidine is metabolized by hepatic CYP450 enzymes.
Acetaminophen: renal excretion of metabolites (glucuronide and sulfate conjugates, ~85-90%), minor parent drug (<5%). Aspirin: renal excretion of salicylate and its metabolites (salicyluric acid, glucuronides, gentisic acid), dose-dependent; at therapeutic doses, ~50-80% as free salicylate and conjugates. Codeine: renal excretion of free and conjugated codeine (about 90%) and metabolites (morphine, norcodeine).
Renal: 60-80% (codeine and metabolites, primarily as codeine-6-glucuronide, norcodeine, and morphine); unchanged codeine <10%. Fecal: <10%. Biliary: minor.
Acetaminophen: 10-25% (albumin). Aspirin: 50-80% (albumin), dose-dependent; salicylate: 75-90% (albumin). Codeine: ~7% (albumin).
Codeine: 7-25% (primarily albumin); pseudoephedrine: negligible (<5%); triprolidine: approximately 85% (mainly albumin).
Acetaminophen: 0.9-1.0 L/kg (large distribution including liver). Aspirin: 0.15-0.2 L/kg (low Vd, confined to plasma and extracellular fluid); salicylate: 0.2-0.3 L/kg. Codeine: 3-6 L/kg (extensive tissue distribution). Clinical meaning: Large Vd for codeine suggests extensive tissue binding; aspirin Vd is small, consistent with limited extravascular distribution.
Codeine: 3-6 L/kg; pseudoephedrine: 2.5-3.5 L/kg; triprolidine: 2-5 L/kg. Indicates extensive tissue distribution.
Oral: Acetaminophen: 85-95%. Aspirin: 40-60% (due to first-pass hydrolysis to salicylate). Codeine: ~50% due to first-pass metabolism.
Codeine: 50-70% (oral); pseudoephedrine: 100% (oral); triprolidine: approximately 50% (oral) due to first-pass metabolism.
GFR 30-59 m L/min: Administer every 6 hours; maximum 6 tablets/day. GFR 15-29 m L/min: Administer every 12 hours; maximum 4 tablets/day. GFR <15 m L/min: Not recommended due to accumulation of codeine metabolites.
GFR 30-59 m L/min: administer every 6 hours; GFR <30 m L/min: administer every 12 hours or avoid use due to risk of accumulation of codeine and pseudoephedrine; hemodialysis: not recommended.
Child-Pugh Class A: No adjustment. Child-Pugh Class B: Reduce dose by 50% and extend interval to every 6 hours; maximum 4 tablets/day. Child-Pugh Class C: Contraindicated.
Child-Pugh A (mild): no adjustment; Child-Pugh B (moderate): reduce dose by 50% or extend interval to every 8 hours; Child-Pugh C (severe): avoid use due to risk of central nervous system depression.
Not recommended for children <12 years due to aspirin risk of Reye syndrome. For children ≥12 years: Dose based on codeine component (0.5-1 mg/kg/dose) with maximum acetaminophen 75 mg/kg/day and aspirin 100 mg/kg/day. Typical: 1 tablet (acetaminophen 300 mg/aspirin 300 mg/codeine 30 mg) every 4-6 hours as needed; max 4 tablets/day.
Not recommended in children <12 years due to risk of respiratory depression. For children ≥12 years: 10 m L orally every 4-6 hours as needed, max 4 doses in 24 hours. Weight-based dosing not established.
Start with lowest effective dose (e.g., 1 tablet every 6 hours); monitor renal and hepatic function; maximum 6 tablets/day due to increased sensitivity and risk of adverse effects.
Start at lower dose (e.g., 5 m L orally every 6 hours) due to increased sensitivity to anticholinergic and sedative effects; monitor for confusion, urinary retention, and hypotension.
Risk of medication errors: confusion between different strengths and concentrations of acetaminophen can result in accidental overdose and fatal hepatotoxicity. Aspirin use in children and teenagers with viral infections is associated with Reye's syndrome.
WARNING: RISKS FROM CONCOMITANT USE WITH BENZODIAZEPINES OR OTHER CNS DEPRESSANTS; ADDICTION, ABUSE, AND MISUSE; RISK EVALUATION AND MITIGATION STRATEGY (REMS); LIFE-THREATENING RESPIRATORY DEPRESSION; ACCIDENTAL INGESTION; NEONATAL OPIOID WITHDRAWAL SYNDROME; CYP2D6 GENETIC VARIABILITY; INTERACTION WITH ALCOHOL; RISKS FROM CONCOMITANT USE OF CYP3A4 INHIBITORS; RISKS IN PATIENTS WITH GASTROINTESTINAL CONDITIONS; RISKS OF USE IN PATIENTS WITH ASTHMA OR OTHER RESPIRATORY DISEASE; LABEL FOR INFANTS AND CHILDREN.
Hepatotoxicity (acetaminophen dose >4 g/day), Reye's syndrome (aspirin in children), respiratory depression (codeine), tolerance/dependence, bleeding risk (aspirin), GI toxicity, renal impairment, hypersensitivity reactions.
Addiction, abuse, and misuse,Life-threatening respiratory depression,Neonatal opioid withdrawal syndrome,Risks from concomitant use with benzodiazepines or other CNS depressants,CYP2D6 genetic variability (ultrarapid metabolizers),Accidental ingestion,Interaction with alcohol,Use in patients with gastrointestinal conditions,Use in patients with asthma or other respiratory disease,Avoid use in children <12 years
Hypersensitivity to any component, active peptic ulcer disease, bleeding disorders, severe hepatic impairment, severe respiratory depression, children with viral illness (aspirin), pregnancy (third trimester for aspirin, codeine cautious).
Hypersensitivity to codeine, triprolidine, or any component,Children <12 years,Postoperative management in children <18 years after tonsillectomy and/or adenoidectomy,Significant respiratory depression,Acute or severe bronchial asthma,Concurrent use of monoamine oxidase inhibitors (MAOIs) or within 14 days,Paralytic ileus,Known CYP2D6 ultrarapid metabolizers
Avoid alcohol due to increased risk of acetaminophen hepatotoxicity and aspirin-induced GI bleeding. Avoid large amounts of caffeine or high-tyramine foods (e.g., aged cheeses, cured meats) as they may affect CYP2D6 metabolism of codeine.
Avoid grapefruit and grapefruit juice as they may increase codeine levels and risk of adverse effects. High-tyramine foods (aged cheese, cured meats, fermented products) may interact with pseudoephedrine, potentially causing hypertensive crisis. Alcohol is contraindicated due to additive CNS depression.
Acetaminophen: Generally considered low risk; association with ASD and ADHD with prolonged use not fully established. Aspirin: First trimester: possible increased risk of gastroschisis; second trimester: relatively safe; third trimester: risk of premature closure of ductus arteriosus, oligohydramnios, and increased peripartum hemorrhage. Codeine: First trimester: possible neural tube defects; second and third trimesters: risk of respiratory depression, withdrawal in neonate with chronic use; neonatal opioid withdrawal syndrome (NOWS) possible.
First trimester: Codeine is associated with increased risk of congenital malformations (OR 1.24–2.0), particularly cardiac defects, with a dose-response relationship. Triprolidine and pseudoephedrine are generally considered low risk, but pseudoephedrine may be associated with gastroschisis (OR 1.8). Second trimester: Codeine may cause fetal dependence; pseudoephedrine may reduce uteroplacental blood flow. Third trimester: Codeine can cause neonatal opioid withdrawal syndrome (NOWS) and respiratory depression at delivery; pseudoephedrine may exacerbate pregnancy-induced hypertension. Overall, avoid in pregnancy for non-severe indications.
Acetaminophen: M/P ratio approximately 0.91-1.42; considered safe. Aspirin: M/P ratio 0.08-0.15; high doses may cause Reye's syndrome; avoid or use low doses. Codeine: M/P ratio about 2.5; variable metabolism; risk of CNS depression in infant; avoid due to potential for toxicity in CYP2D6 ultrarapid metabolizers.
Codeine and pseudoephedrine are excreted into breast milk. M/P ratio for codeine is ~2.5; for pseudoephedrine, ~2.6–3.5. Use is contraindicated in breastfeeding due to risk of neonatal opioid toxicity (especially in CYP2D6 ultra-rapid metabolizers) and potential irritability/poor feeding from pseudoephedrine. Triprolidine has limited data but is considered compatible in low doses.
Acetaminophen: No dose adjustment needed. Aspirin: Avoid in third trimester; use lowest effective dose if necessary. Codeine: Avoid in pregnancy; if used, lowest effective dose for shortest duration; caution for CYP2D6 polymorphism. Pharmacokinetic changes: Increased clearance of codeine during pregnancy may require higher doses but risk outweighs benefit.
No specific dose adjustments are established; however, due to increased renal clearance of pseudoephedrine in pregnancy, standard doses may be less effective. Codeine metabolism via CYP2D6 is variably affected by pregnancy (increased clearance ≈30–50% in second/third trimester), potentially requiring dose titration. Avoid use entirely in pregnancy; use alternative agents if needed.
Combination analgesic with acetaminophen (hepatotoxic at high doses), aspirin (antiplatelet, GI irritant, contraindicated in children <12 due to Reye's syndrome), and codeine (prodrug to morphine via CYP2D6; efficacy depends on CYP2D6 phenotype; risk of CNS/respiratory depression). Avoid in severe hepatic/renal impairment, active peptic ulcer, bleeding disorders, or concomitant use of other CNS depressants. Maximum acetaminophen dose from all sources: 4 g/day.
Actifed w/ Codeine combines triprolidine, pseudoephedrine, and codeine. Due to codeine's prodrug metabolism via CYP2D6, ultra-rapid metabolizers risk toxicity; contraindicated in children <12 years, post-tonsillectomy/adenoidectomy, and breastfeeding. Pseudoephedrine may cause hypertensive crisis with MAOIs. Triprolidine's anticholinergic effects exacerbate glaucoma, urinary retention, and cognitive impairment in elderly.
Do not exceed recommended dose; acetaminophen overdosage can cause serious liver damage.,Do not take with other products containing acetaminophen or aspirin.,Avoid alcohol while taking this medication to reduce risk of liver toxicity and GI bleeding.,This product contains aspirin; do not give to children/teenagers with chickenpox or flu-like symptoms to avoid Reye's syndrome.,May cause drowsiness; do not drive or operate machinery until you know how you react.,Codeine is a narcotic pain reliever with abuse potential; use exactly as prescribed.,Seek medical attention if you experience signs of allergic reaction (rash, difficulty breathing) or bleeding (black/tarry stools, unusual bruising).
Do not exceed recommended dose; risk of serious breathing problems, especially in children.,Avoid alcohol and other CNS depressants (e.g., benzodiazepines, opioids) as they increase sedation and respiratory depression risk.,Store securely; codeine carries risk of dependence and misuse.,If pregnant or breastfeeding, consult prescriber; do not use while breastfeeding due to infant toxicity risk.,May cause drowsiness; avoid driving or operating heavy machinery until effects are known.,Inform healthcare provider of all medications, especially MAOIs (within 14 days), antidepressants, or blood pressure medications.,Discontinue and seek medical help if symptoms of allergic reaction (rash, itching, swelling, severe dizziness, trouble breathing) occur.,Use caution with high blood pressure, thyroid problems, diabetes, or enlarged prostate.
"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."
"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 ACETAMINOPHEN, ASPIRIN, AND CODEINE PHOSPHATE vs ACTIFED W/ CODEINE, answered by our medical review team.
ACETAMINOPHEN, ASPIRIN, AND CODEINE PHOSPHATE is a Opioid Agonist that works by Acetaminophen: cyclooxygenase (COX) inhibitor, primarily central, analgesic and antipyretic. Aspirin: irreversible COX-1 and COX-2 inhibitor, analgesic, anti-inflammatory, antipyretic, antiplatelet. Codeine: prodrug converted to morphine; mu-opioid receptor agonist.. ACTIFED W/ CODEINE is a Opioid Agonist that works by Codeine is a prodrug that is metabolized to morphine, which acts as a mu-opioid receptor agonist; triprolidine is an H1 receptor antagonist. The combination produces antitussive and antihistamine effects.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between ACETAMINOPHEN, ASPIRIN, AND CODEINE PHOSPHATE and ACTIFED W/ CODEINE depend on the specific clinical indication. These are both Opioid Agonist agents and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of ACETAMINOPHEN, ASPIRIN, AND CODEINE PHOSPHATE is: 1-2 tablets (each containing acetaminophen 300 mg, aspirin 300 mg, codeine phosphate 30 mg) orally every 4-6 hours as needed for pain; maximum 8 tablets/day.. The standard adult dose of ACTIFED W/ CODEINE is: Adults: 10 m L orally every 4-6 hours as needed, not to exceed 4 doses in 24 hours. Each 10 m L contains 10 mg codeine, 4 mg triprolidine, 60 mg pseudoephedrine.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
A moderate-severity drug interaction has been identified when combining ACETAMINOPHEN, ASPIRIN, AND CODEINE PHOSPHATE and ACTIFED W/ CODEINE. Codeine, a prodrug converted to morphine via CYP2D6, and metyrosine, a tyrosine hydroxylase inhibitor, synergistically depress the central nervous system. Codeine's mu-opioid receptor agonism and metyrosine's reduction of catecholamine synthesis lead to enhanced sedation, respiratory depression, and hypotension. Clinically, patients may experience excessive drowsiness, confusion, or respiratory compromise, particularly at higher doses or in vulnerable populations. Consult your prescriber before combining these medications.
The maternal-fetal safety profiles differ. ACETAMINOPHEN, ASPIRIN, AND CODEINE PHOSPHATE is classified as Category D/X. Acetaminophen: Generally considered low risk; association with ASD and ADHD with prolonged use not fully established. Aspirin: First trimester: possible increased risk of gastrosch. ACTIFED W/ CODEINE is classified as Category D/X. First trimester: Codeine is associated with increased risk of congenital malformations (OR 1.24–2.0), particularly cardiac defects, with a dose-response relationship. Triprolidine . Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.