Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
ACETAMINOPHEN AND CODEINE PHOSPHATE vs ALTOPREV
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
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.
Competitive inhibitor of HMG-Co A reductase, the rate-limiting enzyme in cholesterol biosynthesis, leading to upregulation of LDL receptors and increased clearance of LDL cholesterol.
Mild to moderate pain,Pain accompanied by fever
Heterozygous familial hypercholesterolemia,Polygenic hypercholesterolemia,Mixed dyslipidemia,Prevention of cardiovascular events (FDA-approved),Primary prevention of coronary heart disease
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.
Lovastatin extended-release: Initial 20, 40, or 60 mg orally once daily at bedtime; titrate every 4 weeks; max 60 mg/day.
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.
14 hours (terminal); extended-release formulation allows once-daily dosing
Acetaminophen: primarily glucuronidation and sulfation in liver; minor CYP450 (CYP2E1) to toxic NAPQI. Codeine: CYP2D6 to morphine; CYP3A4 to norcodeine; glucuronidation.
Primarily hepatic via CYP3A4; also conjugated by glucuronidation. Metabolites include active beta-hydroxy acid.
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.
Renal (10% as active metabolites, 83% as inactive metabolites in urine); fecal (5%)
Acetaminophen: 10–25% (albumin). Codeine: 7–25% (primarily albumin).
91-95% bound to plasma proteins (primarily albumin)
Acetaminophen: 0.9 L/kg. Codeine: 3–6 L/kg (extensive tissue distribution).
0.96 L/kg; indicates distribution into extravascular tissues
Oral: acetaminophen 88% (variable first-pass); codeine 50–60% (first-pass metabolism to morphine, norcodeine, and conjugates).
14-26% for extended-release tablets; food increases rate but not extent of absorption
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.
e GFR 30-80 m L/min: No adjustment. e GFR <30 m L/min: Use with caution, max dose 20 mg/day.
Child-Pugh A: no adjustment; Child-Pugh B: reduce dose by 50% and extend interval to every 8 hours; Child-Pugh C: contraindicated.
Contraindicated in active liver disease or unexplained persistent transaminase elevations. Child-Pugh Class A: No dose adjustment. Child-Pugh Class B or C: Not recommended (no data).
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.
Not approved for patients <20 years (safety and efficacy not established).
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.
Start at low end of dosing range (20 mg/day) due to increased risk of myopathy; monitor renal function and muscle symptoms.
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.
None.
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.
Myopathy/rhabdomyolysis risk, especially with concurrent use of CYP3A4 inhibitors (azole antifungals, macrolide antibiotics, protease inhibitors, grapefruit juice),Hepatic enzyme elevations (monitor transaminases before and during therapy),Use with caution in patients with renal impairment,Avoid in pregnancy and lactation
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.
Active liver disease or unexplained persistent transaminase elevations,Hypersensitivity to lovastatin or any component,Pregnancy,Lactation,Concurrent use of strong CYP3A4 inhibitors (e.g., itraconazole, ketoconazole, posaconazole, voriconazole, erythromycin, clarithromycin, telithromycin, HIV protease inhibitors, boceprevir, telaprevir, nefazodone, cobicistat)
Avoid alcohol; high-fat meals may delay absorption but not clinically significant.
Grapefruit juice increases lovastatin blood levels and risk of toxicity. Avoid grapefruit products. High-fat meals may increase absorption; take with evening meal for optimal effect.
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.
FDA Pregnancy Category X. Contraindicated in pregnancy due to risk of fetal harm (HMG-Co A reductase inhibition may interfere with cholesterol synthesis necessary for fetal development). First trimester: high risk of congenital anomalies, including CNS and skeletal defects. Second and third trimesters: continued risk of fetal toxicity; placental transfer demonstrated in animal studies.
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.
Contraindicated in breastfeeding. HMG-Co A reductase inhibitors may reduce cholesterol levels in breast milk, potentially adverse effects on infant lipid metabolism. M/P ratio not established for lovastatin; limited data suggest low excretion, but risk outweighs benefit.
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.
No dose adjustment applicable; drug is contraindicated in pregnancy. If exposure occurs, discontinue immediately. Pharmacokinetic changes in pregnancy (increased volume of distribution, enhanced clearance) would theoretically reduce efficacy, but no recommendation for dose adjustment due to contraindication.
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.
ALTOPREV (lovastatin extended-release) should be taken with the evening meal to maximize absorption. Avoid grapefruit juice. Monitor liver function and creatine kinase. If used with fibrates, caution for myopathy/rhabdomyolysis. Not recommended in severe renal impairment (Cr Cl <30 m L/min).
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.
Take exactly as prescribed, once daily with the evening meal.,Avoid grapefruit and grapefruit juice during treatment.,Report unexplained muscle pain, tenderness, or weakness.,Avoid alcohol consumption; inform your doctor if you have liver disease.,Routine blood tests are needed to monitor liver function and cholesterol levels.
"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."
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about ACETAMINOPHEN AND CODEINE PHOSPHATE vs ALTOPREV, answered by our medical review team.
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.. ALTOPREV is a HMG-CoA Reductase Inhibitor (Statin) that works by Competitive inhibitor of HMG-Co A reductase, the rate-limiting enzyme in cholesterol biosynthesis, leading to upregulation of LDL receptors and increased clearance of LDL cholesterol.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between ACETAMINOPHEN AND CODEINE PHOSPHATE and ALTOPREV 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 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.. The standard adult dose of ALTOPREV is: Lovastatin extended-release: Initial 20, 40, or 60 mg orally once daily at bedtime; titrate every 4 weeks; max 60 mg/day.. 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 ACETAMINOPHEN AND CODEINE PHOSPHATE and ALTOPREV 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. 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. ALTOPREV is classified as Category C. FDA Pregnancy Category X. Contraindicated in pregnancy due to risk of fetal harm (HMG-CoA reductase inhibition may interfere with cholesterol synthesis necessary for fetal developm. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.