Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
ACTIFED vs OFIRMEV
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
ACTIFED contains triprolidine, a first-generation antihistamine that competitively inhibits histamine H1 receptors, and pseudoephedrine, a sympathomimetic amine that directly stimulates alpha-adrenergic receptors, causing vasoconstriction and decongestion.
OFIRMEV (acetaminophen) is a para-aminophenol derivative with analgesic and antipyretic activity. Its mechanism of action is not fully understood, but it is thought to involve inhibition of cyclooxygenase (COX) enzymes in the central nervous system, with minimal peripheral COX inhibition. It may also act on serotonergic pathways and cannabinoid receptors.
Temporary relief of symptoms associated with allergic rhinitis (sneezing, rhinorrhea, pruritus),Temporary relief of nasal congestion due to common cold, hay fever, or other upper respiratory allergies
Management of mild to moderate pain,Management of moderate to severe pain with adjunctive opioid analgesics,Reduction of fever
1 tablet (pseudoephedrine HCl 60 mg, triprolidine HCl 2.5 mg) orally every 4-6 hours; maximum 4 tablets in 24 hours.
IV: 1000 mg every 6 hours or 650 mg every 4 hours; maximum single dose: 1000 mg; minimum dosing interval: 4 hours; maximum daily dose: 4000 mg.
Triprolidine: 3.2 hours; Pseudoephedrine: 5–8 hours (p H-dependent: alkaline urine prolongs). Terminal half-life for clinical use typically 4–6 hours.
Terminal elimination half-life is 2-3 hours in adults (2.5-3 hours in children). Clinically, dosing every 4-6 hours is needed to maintain therapeutic levels.
Triprolidine: Hepatic metabolism via CYP450 enzymes. Pseudoephedrine: Partially metabolized in liver by N-demethylation; excreted unchanged in urine (70-90%).
Acetaminophen is primarily metabolized in the liver via conjugation with glucuronide (50-60%) and sulfate (20-30%). A minor amount is oxidized by cytochrome P450 (CYP2E1, CYP1A2, CYP3A4) to a toxic reactive metabolite (NAPQI), which is normally detoxified by glutathione. At toxic doses, glutathione is depleted, leading to NAPQI accumulation and hepatotoxicity.
Renal: 80% (20% unchanged, 60% as metabolites). Fecal: 20% (unchanged and metabolites). Active tubular secretion of pseudoephedrine.
Primarily renal (85% as sulfate and glucuronide conjugates, 10% as unchanged drug). Less than 5% fecal/biliary.
Triprolidine: 60% bound to serum albumin; Pseudoephedrine: 20–30% bound to plasma proteins (mainly albumin).
10-25% bound to albumin at therapeutic concentrations.
Triprolidine: 2.5–4.0 L/kg; Pseudoephedrine: 2.6–3.5 L/kg. Indicates extensive tissue distribution.
0.8-1.0 L/kg. Indicates distribution into total body water.
Oral: Triprolidine 90–100%; Pseudoephedrine 100% (first-pass metabolism negligible).
100% (intravenous); not applicable for other routes as OFIRMEV is IV only.
Cr Cl 30-50 m L/min: extend dosing interval to every 8 hours. Cr Cl 15-29 m L/min: every 12 hours. Cr Cl <15 m L/min: not recommended.
No dose adjustment required for GFR ≥30 m L/min. For GFR <30 m L/min, extend dosing interval to every 8 hours; maximum daily dose 3000 mg.
Child-Pugh A: no adjustment. Child-Pugh B: consider extending interval to every 8 hours. Child-Pugh C: avoid use.
Child-Pugh Class A: No adjustment. Child-Pugh Class B: Reduce total daily dose by 50% (max 2000 mg/day). Child-Pugh Class C: Contraindicated or use with extreme caution; reduce dose to 50% of standard and extend interval to every 8 hours; maximum 2000 mg/day.
Children 6-12 years: 1/2 tablet (pseudoephedrine 30 mg, triprolidine 1.25 mg) orally every 6 hours; max 2 tablets/24 hours. Children <6 years: not recommended.
Weight-based: <10 kg: 7.5 mg/kg/dose every 6 hours; 10-50 kg: 15 mg/kg/dose every 6 hours; >50 kg: 1000 mg every 6 hours or 650 mg every 4 hours. Maximum single dose: 15 mg/kg (up to 1000 mg); maximum daily dose: 75 mg/kg (up to 4000 mg).
Start with 1/2 tablet (pseudoephedrine 30 mg, triprolidine 1.25 mg) orally every 8 hours; monitor for CNS excitation and anticholinergic effects.
No specific dose adjustment; consider reduced renal function. For Cr Cl <30 m L/min, extend interval to every 8 hours. Maximum daily dose: 3000 mg in frail elderly or with comorbidities.
None.
Acetaminophen has been associated with cases of acute liver failure, at times resulting in liver transplant and death. Most of the cases of liver injury are associated with the use of acetaminophen at doses that exceed 4000 mg per day, and often involve more than one acetaminophen-containing product.
Cardiovascular effects: hypertension, palpitations, tachycardia, arrhythmias,CNS stimulation: nervousness, dizziness, insomnia, especially in elderly,May cause urinary retention in patients with prostatic hypertrophy,Use caution in patients with diabetes, hyperthyroidism, ischemic heart disease, increased intraocular pressure,Anticholinergic effects: dry mouth, blurred vision, constipation
Risk of serious hepatotoxicity, especially with doses >4000 mg/day or in patients with underlying liver disease,Risk of severe skin reactions (Stevens-Johnson syndrome, toxic epidermal necrolysis, acute generalized exanthematous pustulosis) – discontinue at first sign of rash,Risk of hypersensitivity reactions including anaphylaxis,Use caution in patients with severe hepatic impairment, active hepatic disease, or alcoholism,Avoid concurrent use of other acetaminophen-containing products
Hypersensitivity to triprolidine, pseudoephedrine, or any component,Severe hypertension or coronary artery disease,Monoamine oxidase inhibitor (MAOI) therapy (concurrent or within 14 days),Narrow-angle glaucoma,Urinary retention,During or within 14 days of MAOI use
Known hypersensitivity to acetaminophen or any component of the formulation,Severe hepatic impairment or active liver disease (relative contraindication without black box)
Avoid high-tyramine foods (aged cheese, cured meats, fermented products) as pseudoephedrine may potentiate vasopressor effects. Grapefruit juice may decrease pseudoephedrine absorption; separate administration by at least 4 hours.
No known food interactions. However, avoid excessive alcohol consumption as it may increase the risk of liver damage.
FDA Pregnancy Category C. First trimester: Limited human data; animal studies show fetal toxicity at high doses. Avoid unless benefit outweighs risk. Second/third trimesters: Risk of premature labor, neonatal respiratory depression, and withdrawal symptoms with prolonged use. Use lowest effective dose for shortest duration.
Acetaminophen (OFIRMEV) is generally considered low risk across all trimesters. No increased risk of major congenital anomalies has been consistently demonstrated. Chronic high-dose use in third trimester may be associated with preterm birth or low birth weight. Avoid prolonged use above recommended doses.
Pseudoephedrine is excreted into breast milk; M/P ratio approximately 3.5. Triprolidine is present in milk. Potential for irritability, sleep disturbance in infants; may reduce milk supply. Use with caution; alternative preferred. Discontinue breastfeeding or drug based on necessity.
Acetaminophen is excreted in breast milk in low concentrations (M/P ratio approximately 0.9-1.0). Considered compatible with breastfeeding; peak milk levels occur 1-2 hours after maternal dosing. Use lowest effective dose for shortest duration.
No specific dose adjustment recommended for pregnancy; however, increased plasma volume may reduce drug concentrations. Use lowest effective dose due to limited safety data. Avoid in hypertension or preeclampsia.
No dose adjustment required during pregnancy. Pharmacokinetic changes in pregnancy (increased volume of distribution, clearance) may lead to lower peak concentrations but standard dosing remains effective. Maximum single dose: 1 g; maximum daily dose: 4 g.
Actifed (pseudoephedrine + triprolidine) is contraindicated in patients with severe hypertension, coronary artery disease, or narrow-angle glaucoma. Pseudoephedrine can cause CNS stimulation and insomnia, so avoid evening dosing. Triprolidine is a first-generation antihistamine with significant anticholinergic effects; use caution in elderly or those with BPH, urinary retention, or asthma.
OFIRMEV (acetaminophen) injection is an IV formulation of acetaminophen used for pain and fever management. It is a prodrug that requires no hepatic conversion, providing rapid onset of action. Monitor for hepatotoxicity; maximum daily dose is 4 grams in adults but lower in patients with hepatic impairment or malnutrition. Do not exceed 1 gram per dose. Hypotension and anaphylaxis have been reported. Not interchangeable with oral acetaminophen due to dose equivalency. Use with caution in patients with alcohol use disorder.
Do not take with other cold or allergy medications containing decongestants or antihistamines.,Avoid alcohol and sedatives as they may increase drowsiness.,Do not crush or chew extended-release tablets; swallow whole.,Monitor for increased blood pressure or heart rate; discontinue if palpitations occur.,May cause dizziness; avoid driving or operating heavy machinery until you know how it affects you.
OFIRMEV is given intravenously for pain or fever.,Do not take additional acetaminophen-containing medications while receiving OFIRMEV.,Report any signs of allergic reaction (rash, itching, swelling, trouble breathing).,Seek immediate medical attention if you experience severe abdominal pain, yellowing of skin or eyes, or dark urine.,Inform your healthcare provider about all medications you are taking, especially blood thinners.
No interactions on record
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about ACTIFED vs OFIRMEV, answered by our medical review team.
ACTIFED is a Decongestant/Antihistamine Combination that works by ACTIFED contains triprolidine, a first-generation antihistamine that competitively inhibits histamine H1 receptors, and pseudoephedrine, a sympathomimetic amine that directly stimulates alpha-adrenergic receptors, causing vasoconstriction and decongestion.. OFIRMEV is a Non-opioid Analgesic that works by OFIRMEV (acetaminophen) is a para-aminophenol derivative with analgesic and antipyretic activity. Its mechanism of action is not fully understood, but it is thought to involve inhibition of cyclooxygenase (COX) enzymes in the central nervous system, with minimal peripheral COX inhibition. It may also act on serotonergic pathways and cannabinoid receptors.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between ACTIFED and OFIRMEV 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 ACTIFED is: 1 tablet (pseudoephedrine HCl 60 mg, triprolidine HCl 2.5 mg) orally every 4-6 hours; maximum 4 tablets in 24 hours.. The standard adult dose of OFIRMEV is: IV: 1000 mg every 6 hours or 650 mg every 4 hours; maximum single dose: 1000 mg; minimum dosing interval: 4 hours; maximum daily dose: 4000 mg.. 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 ACTIFED and OFIRMEV 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. ACTIFED is classified as Category C. FDA Pregnancy Category C. First trimester: Limited human data; animal studies show fetal toxicity at high doses. Avoid unless benefit outweighs risk. Second/third trimesters: Risk . OFIRMEV is classified as Category C. Acetaminophen (OFIRMEV) is generally considered low risk across all trimesters. No increased risk of major congenital anomalies has been consistently demonstrated. Chronic high-dos. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.