Comparative Pharmacology
Head-to-head clinical analysis: DURAPHYL versus SOMOPHYLLIN T.
Head-to-head clinical analysis: DURAPHYL versus SOMOPHYLLIN T.
DURAPHYL vs SOMOPHYLLIN-T
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.
Theophylline is a methylxanthine that inhibits phosphodiesterase, leading to increased intracellular cAMP levels, causing bronchodilation, and also acts as an adenosine receptor antagonist.
5 mg orally twice daily, increased to 10 mg twice daily after one week if tolerated; maximum dose 20 mg twice daily.
Oral: 200-400 mg twice daily (12-hourly). Dose titration: start 200 mg twice daily, increase by 200 mg/day every 3 days as tolerated to achieve serum theophylline level 5-15 mcg/mL. Maximum: 800 mg/day or 400 mg twice daily.
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.
Terminal elimination half-life is approximately 8 hours in healthy adults (range 3-13 hours). In neonates, it is prolonged (20-30 h). In smokers, half-life is reduced to 4-5 h. In patients with hepatic cirrhosis or heart failure, half-life may exceed 24 hours.
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.
Approximately 90% is eliminated via hepatic metabolism (primarily via CYP1A2, CYP3A4), and about 10% is excreted unchanged in the urine. Renal clearance accounts for <10% of total clearance in adults. Biliary/fecal excretion is minimal (less than 5%).
Category C
Category C
Bronchodilator
Bronchodilator