Comparative Pharmacology
Head-to-head clinical analysis: SOMOPHYLLIN T versus THEOPHYL SR.
Peer-Reviewed Evidence
Head-to-head clinical analysis: SOMOPHYLLIN T versus THEOPHYL SR.
SOMOPHYLLIN-T vs THEOPHYL-SR
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Theophylline is a methylxanthine that inhibits phosphodiesterase, leading to increased intracellular cAMP levels, causing bronchodilation, and also acts as an adenosine receptor antagonist.
Theophylline is a methylxanthine that inhibits phosphodiesterase, increasing cyclic AMP levels, and antagonizes adenosine receptors, leading to bronchodilation and anti-inflammatory effects.
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.
300 mg orally every 12 hours, with dosing titrated to achieve serum trough concentrations of 5-15 mcg/mL.
None Documented
None Documented
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.
Adults: 8-10 hours (range 3-12); Neonates: 20-30 hours; Smokers: 4-5 hours; Cirrhosis: 30-40 hours. Dose adjustments needed based on half-life variations.
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%).
Renal: ~10% unchanged; Hepatic metabolism (90%) via CYP1A2, 3A4; metabolites (caffeine, 3-methylxanthine) excreted renally. Total clearance predominantly hepatic.
Category C
Category C
Bronchodilator
Bronchodilator