NAPROXEN SODIUM AND PSEUDOEPHEDRINE HYDROCHLORIDE
Clinical safety rating: safe
Animal studies have demonstrated safety
Naproxen sodium is a nonsteroidal anti-inflammatory drug (NSAID) that inhibits cyclooxygenase (COX-1 and COX-2), reducing prostaglandin synthesis, leading to anti-inflammatory, analgesic, and antipyretic effects. Pseudoephedrine hydrochloride is a sympathomimetic amine that acts as a direct and indirect alpha-adrenergic agonist, causing vasoconstriction and decongestion of nasal mucosa.
| Metabolism | Naproxen: primarily metabolized by hepatic CYP2C9 to inactive metabolites. Pseudoephedrine: partially metabolized by hepatic N-demethylation (CYP2B6, CYP2C19); predominantly excreted unchanged in urine. |
| Excretion | Naproxen: ~95% renal (primarily as unchanged drug and conjugates), <5% biliary. Pseudoephedrine: 70-90% renal (unchanged), remainder hepatic metabolism. |
| Half-life | Naproxen: 12-17 hours (terminal), allowing twice-daily dosing; prolonged in elderly or renal impairment. Pseudoephedrine: 4-6 hours (pH-dependent; shorter with acidic urine, prolonged with alkaline urine). |
| Protein binding | Naproxen: >99% bound to albumin. Pseudoephedrine: negligible (<20%) binding to plasma proteins. |
| Volume of Distribution | Naproxen: 0.16 L/kg. Pseudoephedrine: 2.5-4 L/kg, indicating extensive tissue distribution. |
| Bioavailability | Oral: Naproxen 95% (fasted); Pseudoephedrine 100% (immediate-release). |
| Onset of Action | Oral: Naproxen 1-2 hours (analgesic); Pseudoephedrine 30-60 minutes (decongestant). |
| Duration of Action | Naproxen: 7-12 hours (analgesic/anti-inflammatory). Pseudoephedrine: 4-6 hours (immediate-release); extended-release formulations up to 12 hours. |
One tablet (naproxen sodium 220 mg/pseudoephedrine HCl 120 mg) orally every 12 hours; maximum 2 tablets in 24 hours. For extended-release formulations: one tablet (naproxen sodium 440 mg/pseudoephedrine HCl 240 mg) orally every 12 hours; maximum 2 tablets in 24 hours.
| Dosage form | TABLET, EXTENDED RELEASE |
| Renal impairment | Contraindicated in GFR <30 mL/min. For GFR 30-59 mL/min: use with caution, reduce naproxen dose by 50% or avoid; consider shortest duration. For GFR ≥60 mL/min: no adjustment necessary. |
| Liver impairment | Child-Pugh Class A: no adjustment. Child-Pugh Class B: reduce naproxen dose by 50%; avoid use if possible. Child-Pugh Class C: contraindicated. |
| Pediatric use | Not recommended for children under 12 years. For children ≥12 years: same as adult dosing (one tablet every 12 hours). Weight-based naproxen alone: 5-7 mg/kg/dose every 8-12 hours, max 15 mg/kg/day; pseudoephedrine: 4 mg/kg/day divided every 6 hours, max 240 mg/day. Use fixed-dose combination only if both components are needed. |
| Geriatric use | Avoid use in patients ≥65 years due to increased risk of gastrointestinal bleeding, renal impairment, and cardiovascular events. If necessary, use lowest effective dose for shortest duration; monitor renal function and blood pressure closely. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
MAOIs can cause hypertensive crisis Can cause insomnia and tachycardia.
| Breastfeeding | Naproxen excreted into breast milk in low amounts (M/P ratio ~0.01); pseudoephedrine excreted in breast milk with M/P ratio ~1.5. Potential for irritability, tachycardia, and reduced milk supply. Caution advised; avoid in breastfeeding if possible. |
| Teratogenic Risk | First trimester: NSAID use associated with increased risk of miscarriage and cardiac defects (limited data). Second trimester: Generally considered low risk; NSAIDs may cause oligohydramnios. Third trimester: Avoid due to risk of premature ductus arteriosus closure, oligohydramnios, and fetal renal impairment; pseudoephedrine may cause fetal tachycardia and potential uteroplacental vasoconstriction. |
■ FDA Black Box Warning
Cardiovascular thrombotic events: NSAIDs increase the risk of serious cardiovascular thrombotic events, myocardial infarction, and stroke, which can be fatal. Risk may increase with duration of use and in patients with cardiovascular disease or risk factors. Contraindicated for treatment of perioperative pain in coronary artery bypass graft (CABG) surgery.
| Common Effects | Insomnia |
| Serious Effects |
Hypersensitivity to naproxen, pseudoephedrine, or any component; history of asthma, urticaria, or allergic-type reactions after aspirin or other NSAIDs; perioperative pain in CABG surgery; severe hypertension; coronary artery disease; concomitant use with MAO inhibitors or within 14 days of stopping such therapy; narrow-angle glaucoma; urinary retention; uncontrolled hyperthyroidism.
| Precautions | Cardiovascular thrombotic events; gastrointestinal bleeding, ulceration, and perforation; hypertension; renal toxicity; anaphylactic reactions; skin reactions (e.g., Stevens-Johnson syndrome); exacerbation of asthma; caution in elderly, hepatic or renal impairment; fluid retention; use with alcohol or other NSAIDs increases risk of GI bleeding; avoid concomitant use with other sympathomimetics. |
Loading safety data…
| Fetal Monitoring | Monitor fetal heart rate, amniotic fluid volume (ultrasound), and uterine contractions during third-trimester exposure. Assess maternal blood pressure for pseudoephedrine effects. In neonates, observe for signs of NSAID toxicity (e.g., gastrointestinal bleeding, renal impairment). |
| Fertility Effects | Naproxen may impair fertility by inhibiting ovulation in women (reversible on discontinuation) and may affect spermatogenesis in animal studies. Pseudoephedrine has no known significant fertility effects. |