SUDAFED 24 HOUR
Clinical safety rating: caution
Comprehensive clinical and safety monograph for SUDAFED 24 HOUR (SUDAFED 24 HOUR).
Pseudoephedrine is a sympathomimetic amine that acts as a decongestant by stimulating alpha-adrenergic receptors in the respiratory tract mucosa, causing vasoconstriction and reducing nasal congestion.
| Metabolism | Primarily hepatic via N-demethylation to active metabolite (norpseudoephedrine); also undergoes oxidative metabolism. CYP450 enzymes involved include CYP2D6. |
| Excretion | Renal 70-90% unchanged; minor hepatic metabolism to inactive metabolites; biliary/fecal excretion negligible (<5%) |
| Half-life | Terminal elimination half-life 9-16 hours (mean 11 hours) in adults; prolonged in renal impairment (up to 24-30 hours in severe insufficiency); clinically relevant for dosing interval (every 24 hours) |
| Protein binding | Low, approximately 20-30%; primarily binds to albumin |
| Volume of Distribution | 2.6-3.5 L/kg; suggests extensive tissue distribution (highly lipophilic) |
| Bioavailability | Oral: 100% (well absorbed); extended-release formulation designed for once-daily dosing |
| Onset of Action | Oral: 30 minutes to 1 hour for decongestant effect (pseudoephedrine 120 mg extended-release) |
| Duration of Action | 12-24 hours (single 120 mg extended-release formulation); decongestant effect typically persists for full dosing interval; clinical note: maximal effect at 4-6 hours post-dose |
120 mg orally every 24 hours (extended-release tablet).
| Dosage form | TABLET, EXTENDED RELEASE |
| Renal impairment | GFR 30-50 mL/min: 120 mg every 24 hours; GFR <30 mL/min: not recommended. |
| Liver impairment | No adjustment necessary; monitor for adverse effects in Child-Pugh C. |
| Pediatric use | Children 6-11 years: 60 mg orally every 24 hours (extended-release tablet). |
| Geriatric use | Start with 60 mg orally every 24 hours; increase gradually based on response and tolerability. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
Comprehensive clinical and safety monograph for SUDAFED 24 HOUR (SUDAFED 24 HOUR).
| Breastfeeding | Pseudoephedrine is excreted in breast milk (M/P ratio ~3.3). May reduce milk production. Use with caution; monitor infant for irritability and sleep disturbances. |
| Teratogenic Risk | First trimester: No evidence of major malformations in human studies. Second and third trimesters: Potential for uterine vasoconstriction and reduced placental perfusion; may cause fetal tachycardia or arrhythmias. Use only if benefit outweighs risk. |
| Fetal Monitoring |
■ FDA Black Box Warning
None.
| Serious Effects |
Severe hypertension, coronary artery disease, narrow-angle glaucoma, urinary retention, concurrent MAOI therapy or within 14 days, hypersensitivity to pseudoephedrine.
| Precautions | May cause hypertension, palpitations, tachycardia, arrhythmias, and stroke; use with caution in patients with cardiovascular disease, hypertension, hyperthyroidism, diabetes, or prostatic hypertrophy; avoid in patients with severe hypertension or coronary artery disease; risk of drug dependence with long-term use; avoid use with MAOIs or within 14 days of MAOI therapy. |
Loading safety data…
| Monitor maternal blood pressure and heart rate. Fetal heart rate monitoring recommended if used in late pregnancy. Assess for signs of uterine hyperstimulation or reduced fetal movements. |
| Fertility Effects | No significant effects on fertility reported in animal studies. Human data lacking. |