Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
UPTRAVI vs OFIRMEV
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Uptravi (selexipag) is a prostacyclin receptor (IP receptor) agonist. Selexipag and its active metabolite, ACT-333679, selectively bind to the IP receptor, leading to vasodilation, inhibition of platelet aggregation, and antiproliferative effects on smooth muscle cells.
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.
Treatment of pulmonary arterial hypertension (PAH, WHO Group I) to delay disease progression and reduce the risk of hospitalization,Off-label: None established
Management of mild to moderate pain,Management of moderate to severe pain with adjunctive opioid analgesics,Reduction of fever
Initial dose 200 mcg orally twice daily, titrated in increments of 200 mcg twice daily at weekly intervals to a maximum of 1600 mcg twice daily.
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.
Terminal elimination half-life is approximately 7–9 hours in healthy subjects, but prolonged in patients with hepatic impairment (Child-Pugh class A: ~11 hours; class B: ~16 hours). Steady-state is reached within 2–4 days of twice-daily dosing.
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.
Selexipag is hydrolyzed by carboxylesterases (mainly CES1 and CES2) to its active metabolite, ACT-333679. Both are further metabolized by CYP3A4 and CYP2C8. ACT-333679 is also a substrate for UGT1A3 and UGT2B7.
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.
Primarily hepatic metabolism; renal excretion of unchanged drug is <1%. Fecal excretion accounts for approximately 70% of total elimination, mainly as metabolites. Biliary excretion contributes to fecal elimination.
Primarily renal (85% as sulfate and glucuronide conjugates, 10% as unchanged drug). Less than 5% fecal/biliary.
99% bound to plasma proteins, primarily to albumin and alpha-1-acid glycoprotein.
10-25% bound to albumin at therapeutic concentrations.
Approximately 0.3 L/kg in healthy subjects, indicating distribution primarily within the vascular space and well-perfused tissues.
0.8-1.0 L/kg. Indicates distribution into total body water.
Oral bioavailability is approximately 50–60% due to first-pass metabolism. Food does not significantly affect absorption.
100% (intravenous); not applicable for other routes as OFIRMEV is IV only.
No dose adjustment required for mild to moderate renal impairment (e GFR ≥15 m L/min/1.73 m²). Not studied in severe renal impairment (e GFR <15 m L/min/1.73 m²) or on dialysis; use caution.
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.
Mild hepatic impairment (Child-Pugh A): No dose adjustment. Moderate hepatic impairment (Child-Pugh B): Initial dose 200 mcg once daily, titrate cautiously. Severe hepatic impairment (Child-Pugh C): Not recommended.
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.
Not indicated for pediatric patients; safety and efficacy not established in patients <18 years.
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).
No specific dose adjustment recommended; elderly patients may have increased sensitivity, monitor closely.
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.
Pulmonary edema may occur; consider the possibility of pulmonary veno-occlusive disease (PVOD) if symptoms develop,Hepatic impairment: Avoid use in severe hepatic impairment (Child-Pugh Class C),Concomitant use with strong CYP2C8 inhibitors (e.g., gemfibrozil) increases exposure; reduce dose or consider alternative,Concomitant use with strong CYP3A4 inducers (e.g., rifampin) may reduce efficacy; monitor for loss of effect
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
Severe hepatic impairment (Child-Pugh Class C),Concomitant use with strong CYP2C8 inhibitors (e.g., gemfibrozil)
Known hypersensitivity to acetaminophen or any component of the formulation,Severe hepatic impairment or active liver disease (relative contraindication without black box)
Avoid grapefruit juice as it may increase systemic exposure to UPTRAVI. Take with or without food, but consistent timing with meals is recommended to maintain stable drug levels.
No known food interactions. However, avoid excessive alcohol consumption as it may increase the risk of liver damage.
In animal studies, UPTRAVI (selexipag) and its active metabolite showed developmental toxicity including reduced fetal weights and increased skeletal variations at maternal toxic doses. No adequate and well-controlled studies in pregnant women. Risk cannot be ruled out. First trimester: potential teratogenicity based on animal data. Second and third trimesters: may cause fetal harm due to pharmacological action (IP receptor agonist) potentially affecting uterine blood flow.
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.
No data on presence in human milk, effects on breastfed infant, or milk production. M/P ratio is unknown. The active metabolite is potentially excreted in animal milk. Due to potential for serious adverse reactions, breastfeeding is not recommended during treatment and for at least 2 days after final dose.
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 pharmacokinetic studies in pregnant women. Pregnancy may alter drug metabolism (e.g., increased clearance, Vd). No specific dose adjustment recommendations; use only if benefit outweighs risk. Close clinical monitoring for efficacy and tolerability.
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.
Titrate to maximum tolerated dose up to 1600 mg twice daily. Monitor for signs of pulmonary edema (PPH with veno-occlusive disease). Co-administration with strong CYP2C8 inhibitors (e.g., gemfibrozil) reduces UPTRAVI clearance; decrease dose by 50% during co-administration. Avoid abrupt discontinuation; taper if possible. May cause orthostatic hypotension; assess blood pressure regularly. UPTRAVI is a prodrug of the active metabolite ACT-333679, a selective prostacyclin receptor (IP receptor) agonist.
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.
Take exactly as prescribed; do not crush or split tablets.,Do not stop taking this medication suddenly; consult your doctor if you need to discontinue.,Avoid grapefruit juice as it may increase drug exposure.,Report any severe headaches, jaw pain, or flushing to your healthcare provider.,Use caution when driving or operating machinery until you know how this medication affects you.,Store at room temperature away from moisture and heat.
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 UPTRAVI vs OFIRMEV, answered by our medical review team.
UPTRAVI is a Prostacyclin Receptor Agonist that works by Uptravi (selexipag) is a prostacyclin receptor (IP receptor) agonist. Selexipag and its active metabolite, ACT-333679, selectively bind to the IP receptor, leading to vasodilation, inhibition of platelet aggregation, and antiproliferative effects on smooth muscle cells.. 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 UPTRAVI 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 UPTRAVI is: Initial dose 200 mcg orally twice daily, titrated in increments of 200 mcg twice daily at weekly intervals to a maximum of 1600 mcg twice daily.. 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 UPTRAVI 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. UPTRAVI is classified as Category C. In animal studies, UPTRAVI (selexipag) and its active metabolite showed developmental toxicity including reduced fetal weights and increased skeletal variations at maternal toxic d. 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.