Comparative Pharmacology
Head-to-head clinical analysis: DURAPHYL versus MAXAIR.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DURAPHYL versus MAXAIR.
DURAPHYL vs MAXAIR
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Bronchodilator via beta-2 adrenergic receptor agonism; increases cAMP, relaxes bronchial smooth muscle.
Beta-2 adrenergic receptor agonist; relaxes bronchial smooth muscle via increased intracellular cAMP.
5 mg orally twice daily, increased to 10 mg twice daily after one week if tolerated; maximum dose 20 mg twice daily.
2 inhalations (340 mcg) via oral inhalation every 4-6 hours as needed for bronchospasm; not to exceed 12 inhalations per day.
None Documented
None Documented
Terminal elimination half-life is 7–9 hours in adults with normal hepatic function; prolonged to 20–30 hours in hepatic cirrhosis or heart failure. In neonates, half-life may exceed 30 hours due to immature CYP450 enzymes.
3.5–4.0 hours; clinically, this supports dosing every 4–6 hours as needed.
Primarily hepatic metabolism (CYP1A2, CYP3A4) with renal excretion of metabolites. Less than 10% excreted unchanged in urine; approximately 70% recovered in urine as metabolites, 30% in feces.
Renal excretion of unchanged drug accounts for approximately 90% of elimination; fecal excretion is minimal (<5%).
Category C
Category C
Bronchodilator
Bronchodilator