Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
DIMETANE-DX vs ACETAMINOPHEN, ASPIRIN AND CAFFEINE
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Dimetane-DX contains brompheniramine (first-generation antihistamine) and dextromethorphan (NMDA receptor antagonist and sigma-1 agonist). Brompheniramine antagonizes histamine at H1 receptors, reducing allergic symptoms; dextromethorphan suppresses cough by acting on the cough center in the medulla oblongata via NMDA receptor antagonism and sigma-1 receptor activation.
Acetaminophen: weak COX-1/2 inhibitor, analgesic and antipyretic through central action; Aspirin: irreversible COX-1/2 inhibitor, anti-inflammatory, analgesic, antipyretic, antiplatelet; Caffeine: adenosine receptor antagonist, CNS stimulant, enhances analgesic effect.
Relief of cough and upper respiratory symptoms associated with allergy or common cold (FDA-approved OTC use)
FDA-approved: Temporary relief of minor aches and pains (headache, muscle ache, toothache, backache, menstrual cramps), reduction of fever.,Off-label: None commonly accepted.
Adults and children ≥12 years: One tablet (brompheniramine 4 mg, dextromethorphan 10 mg, phenylephrine 10 mg) orally every 4 hours as needed, not to exceed 4 doses in 24 hours.
1-2 tablets (250 mg acetaminophen, 250 mg aspirin, 65 mg caffeine per tablet) orally every 4-6 hours as needed for pain or fever; maximum 8 tablets per 24 hours.
Brompheniramine: 25-30 hours; guaifenesin: 1 hour; dextromethorphan: 2-4 hours (CYP2D6 extensive metabolizers) or 20-40 hours (poor metabolizers).
Acetaminophen: 2-4 hours (prolonged in liver disease); aspirin: 15-20 minutes (active metabolite salicylate: 2-3 hours at low doses, prolonged to 15-30 hours at high doses); caffeine: 3-6 hours (prolonged in pregnancy, liver disease).
Brompheniramine is hepatically metabolized via CYP450 enzymes (primarily CYP2D6). Dextromethorphan is extensively metabolized by CYP2D6 to dextrorphan (active metabolite).
Acetaminophen: primarily hepatic via glucuronidation (UGT1A1, UGT1A6, UGT1A9), sulfation (SULT1A1), and minor CYP2E1 (toxic metabolite NAPQI); Aspirin: hydrolyzed to salicylate, further metabolized by conjugation (glycine, glucuronic acid) and oxidation; Caffeine: hepatic via CYP1A2 (major), CYP2E1, CYP3A4, N-acetyltransferase.
Renal: 50-70% (brompheniramine) as metabolites and unchanged drug; guaifenesin metabolites primarily renal; dextromethorphan and metabolites renal. Biliary/fecal: minor.
Acetaminophen: renal elimination of metabolites (glucuronide 60%, sulfate 30%, cysteine/mercapturate 8%, unchanged 2%); aspirin: renal elimination of salicylate and metabolites (75% salicyluric acid, 10% glucuronides, 10% salicylate); caffeine: renal elimination of metabolites (paraxanthine, theobromine, theophylline; <3% unchanged). Total: >95% renal.
Brompheniramine: 50-60% to albumin; guaifenesin: <5%; dextromethorphan: 60-70% to albumin.
Acetaminophen: 10-25% (albumin); aspirin: 80-90% (albumin, decreased at high doses); caffeine: 35% (albumin).
Brompheniramine: 1.5-2.0 L/kg; guaifenesin: 0.5-1.0 L/kg; dextromethorphan: 5-10 L/kg.
Acetaminophen: 0.9-1.0 L/kg; aspirin: 0.15-0.2 L/kg (low); caffeine: 0.6-0.8 L/kg. Reflects distribution into total body water.
Oral: brompheniramine 50-70%, guaifenesin 70-90%, dextromethorphan 40-60% (first-pass metabolism).
Acetaminophen: oral 85-98%; aspirin: oral 50-80% (due to first-pass hydrolysis); caffeine: oral ~100%.
e GFR 30–59 m L/min: Administer with caution and reduce frequency to every 6 hours. e GFR <30 m L/min: Avoid use due to risk of accumulation of dextromethorphan and phenylephrine.
Contraindicated in severe renal impairment (Cr Cl <10 m L/min). For Cr Cl 10-50 m L/min: avoid aspirin component; consider alternative therapy. For Cr Cl >50 m L/min: no adjustment needed for acetaminophen; aspirin may require dose reduction or monitoring.
Child-Pugh Class A: No adjustment. Child-Pugh Class B: Reduce dosing interval to every 8 hours; use with caution. Child-Pugh Class C: Contraindicated due to extensive first-pass metabolism.
Child-Pugh A: caution with acetaminophen (max 2 g/day) and avoid caffeine if severe. Child-Pugh B: avoid aspirin; reduce acetaminophen dose (max 2 g/day) and limit caffeine. Child-Pugh C: contraindicated due to aspirin and acetaminophen risk.
Children 6–11 years: 5 m L (half the adult dose) of liquid formulation (brompheniramine 2 mg, dextromethorphan 5 mg, phenylephrine 5 mg per 5 m L) orally every 4 hours, max 4 doses/day. Children 2–5 years: 2.5 m L orally every 4 hours, max 4 doses/day. Children <2 years: Contraindicated.
Not recommended for children <12 years due to aspirin risk of Reye's syndrome. For adolescents ≥12 years: same as adult dosing: 1-2 tablets every 4-6 hours, max 8 tablets/24 hours.
Age ≥65 years: Initiate at half the adult dose (e.g., one tablet every 8 hours) due to increased anticholinergic effects and risk of urinary retention, constipation, and dizziness. Avoid in frail elderly or those with cognitive impairment.
Caution due to increased sensitivity to aspirin (GI bleeding, renal impairment) and caffeine (insomnia, tachycardia). Start at low end of dosing: 1 tablet every 6 hours; monitor renal function and avoid long-term use.
None.
Reye syndrome warning: Aspirin should not be used in children or teenagers with viral illnesses due to risk of Reye syndrome.
Do not use with MAOIs or for 2 weeks after stopping MAOIs due to risk of serotonin syndrome (dextromethorphan).,Avoid use in patients with asthma, chronic bronchitis, emphysema, or persistent cough (may suppress cough reflex).,Use with caution in patients with glaucoma, prostatic hyperplasia, urinary retention, or hypertension (brompheniramine anticholinergic effects).,CNS depression risk: may cause drowsiness; avoid alcohol or other sedatives.
Hepatotoxicity (acetaminophen overdose), gastrointestinal bleeding (aspirin), Reye syndrome (aspirin in children with viral illness), cardiovascular risk (aspirin may increase bleeding), caffeine-related CNS stimulation, risk of dependence.
Concurrent MAOI therapy or within 14 days,Neonates or premature infants (brompheniramine),Breastfeeding (may suppress lactation; dextromethorphan safety not established),Severe hypertension or coronary artery disease (brompheniramine may increase heart rate)
Hypersensitivity to any component; active peptic ulcer disease; bleeding disorders; severe hepatic impairment; children/adolescents with viral illness (Reye syndrome); third trimester of pregnancy (aspirin); concurrent use of other salicylates or NSAIDs; severe renal impairment.
Avoid concurrent use of tyramine-rich foods (e.g., aged cheeses, cured meats, soy sauce, fermented foods) due to risk of hypertensive crisis with sympathomimetic (phenylephrine). Grapefruit juice may increase dextromethorphan levels; avoid large amounts.
Alcohol increases risk of hepatotoxicity with acetaminophen and GI bleeding with aspirin. Caffeine-containing foods or beverages should be limited to avoid excessive caffeine intake. High-tyramine foods (e.g., aged cheeses, cured meats) may potentiate caffeine effects; no significant interaction documented.
Dimetane-DX contains brompheniramine (antihistamine) and dextromethorphan (antitussive). First trimester: Limited human data; animal studies show no teratogenicity at therapeutic doses. Second and third trimesters: Avoid due to risk of neonatal respiratory depression, withdrawal symptoms, and anticholinergic effects. Dextromethorphan: No clear teratogenic risk, but avoid use. Overall: Contraindicated in pregnancy unless benefit outweighs risk.
First trimester: Aspirin is associated with increased risk of neural tube defects and cardiac malformations; acetaminophen is considered low risk but some studies suggest possible association with gastroschisis. Second trimester: Aspirin may increase risk of intracranial hemorrhage; acetaminophen and caffeine generally not linked to major malformations. Third trimester: Aspirin use is contraindicated due to risk of premature ductus arteriosus closure and oligohydramnios; high-dose acetaminophen may cause oligohydramnios; caffeine metabolism slows, but moderate intake appears safe; chronic high-dose caffeine may be associated with low birth weight.
Brompheniramine may suppress lactation and cause irritability in infants. Dextromethorphan is excreted in breast milk in small amounts (M/P ratio not well defined). Use with caution; consider alternative therapy.
Acetaminophen: M/P ratio approximately 0.9; small amounts excreted; considered safe. Aspirin: M/P ratio variable, typically 0.12-0.42; avoid high doses due to risk of Reye's syndrome; single doses unlikely harmful. Caffeine: M/P ratio approximately 0.5-1.0; moderate intake (≤300 mg/day) considered safe; excessive intake may cause irritability in infant.
No specific dose adjustments are recommended for Dimetane-DX in pregnancy due to limited data. However, increased plasma volume and altered drug metabolism may reduce efficacy; clinicians should consider lowest effective dose and shortest duration. Avoid near delivery.
Acetaminophen: No dose adjustment needed; standard dosing (650-1000 mg every 4-6 hours, max 3000 mg/day). Aspirin: Avoid doses >81 mg/day in third trimester; use lowest effective dose. Caffeine: Metabolism prolonged; limit to ≤200 mg/day (approximately 2 cups coffee).
DIMETANE-DX combines brompheniramine (first-generation antihistamine), phenylephrine (decongestant), and dextromethorphan (antitussive). Avoid in hypertension, MAOI use, or asthma. Monitor for CNS depression and anticholinergic effects.
Acetaminophen, aspirin, and caffeine combination is used for mild to moderate pain and fever reduction. Aspirin component provides anti-inflammatory effects; caution in patients with bleeding disorders or those on anticoagulants due to increased bleeding risk. Acetaminophen hepatotoxicity risk with doses >4g/day or in liver disease. Caffeine may cause insomnia, tremor, or palpitations; avoid in patients with anxiety disorders. Reye syndrome risk with aspirin use in children with viral illnesses. Monitor renal function in elderly or dehydrated patients.
Do not drive or operate machinery until you know how this medication affects you; it may cause drowsiness or dizziness.,Avoid alcohol and other sedatives; they increase sedation and CNS depression.,Do not exceed recommended dosage or use for more than 7 days for cough.,Stop use and consult a doctor if symptoms persist or worsen, or if you develop fever, rash, or persistent headache.,Inform your healthcare provider if you have high blood pressure, heart disease, glaucoma, or urinary retention.
Do not exceed recommended dose; acetaminophen overdose can cause liver damage.,Avoid alcohol while taking this medication.,Do not use in children or teenagers with viral illnesses due to Reye syndrome risk.,May cause stomach upset; take with food or milk.,Limit caffeine intake from other sources when using this medication.
No interactions on record
"Triamterene, a potassium-sparing diuretic, can inhibit the hepatic metabolism of caffeine by competing for cytochrome P450 (CYP) 1A2, the primary enzyme responsible for caffeine clearance. This leads to increased plasma caffeine concentrations and prolonged caffeine half-life, potentially causing caffeine toxicity manifesting as nervousness, insomnia, tachycardia, and diuresis enhancement. Patients may experience exaggerated stimulant effects and increased risk of cardiac arrhythmias when combining these agents."
"Caffeine inhibits the metabolism of sulfadiazine by competitively antagonizing cytochrome P450 (CYP) enzymes, particularly CYP1A2, leading to increased plasma concentrations of sulfadiazine. This elevates the risk of dose-dependent adverse effects, including crystalluria, nephrotoxicity, and hypersensitivity reactions. The interaction may also reduce the therapeutic efficacy of sulfadiazine due to altered pharmacokinetics."
"Caffeine inhibits the cytochrome P450 enzyme CYP2C9, which is primarily responsible for the metabolism of losartan to its active metabolite E-3174. This inhibition can lead to increased plasma concentrations of losartan and decreased formation of the active metabolite, potentially reducing losartan's antihypertensive efficacy. The clinical outcome may be suboptimal blood pressure control in patients consuming high amounts of caffeine."
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about DIMETANE-DX vs ACETAMINOPHEN, ASPIRIN AND CAFFEINE, answered by our medical review team.
DIMETANE-DX is a Antitussive Combination that works by Dimetane-DX contains brompheniramine (first-generation antihistamine) and dextromethorphan (NMDA receptor antagonist and sigma-1 agonist). Brompheniramine antagonizes histamine at H1 receptors, reducing allergic symptoms; dextromethorphan suppresses cough by acting on the cough center in the medulla oblongata via NMDA receptor antagonism and sigma-1 receptor activation.. ACETAMINOPHEN, ASPIRIN AND CAFFEINE is a NSAID / Antiplatelet that works by Acetaminophen: weak COX-1/2 inhibitor, analgesic and antipyretic through central action; Aspirin: irreversible COX-1/2 inhibitor, anti-inflammatory, analgesic, antipyretic, antiplatelet; Caffeine: adenosine receptor antagonist, CNS stimulant, enhances analgesic effect.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between DIMETANE-DX and ACETAMINOPHEN, ASPIRIN AND CAFFEINE 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 DIMETANE-DX is: Adults and children ≥12 years: One tablet (brompheniramine 4 mg, dextromethorphan 10 mg, phenylephrine 10 mg) orally every 4 hours as needed, not to exceed 4 doses in 24 hours.. The standard adult dose of ACETAMINOPHEN, ASPIRIN AND CAFFEINE is: 1-2 tablets (250 mg acetaminophen, 250 mg aspirin, 65 mg caffeine per tablet) orally every 4-6 hours as needed for pain or fever; maximum 8 tablets per 24 hours.. 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 DIMETANE-DX and ACETAMINOPHEN, ASPIRIN AND CAFFEINE 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. DIMETANE-DX is classified as Category C. Dimetane-DX contains brompheniramine (antihistamine) and dextromethorphan (antitussive). First trimester: Limited human data; animal studies show no teratogenicity at therapeutic d. ACETAMINOPHEN, ASPIRIN AND CAFFEINE is classified as Category D/X. First trimester: Aspirin is associated with increased risk of neural tube defects and cardiac malformations; acetaminophen is considered low risk but some studies suggest possible . Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.