Comparative Pharmacology
Head-to-head clinical analysis: SOMOPHYLLIN DF versus SOMOPHYLLIN T.
Peer-Reviewed Evidence
Head-to-head clinical analysis: SOMOPHYLLIN DF versus SOMOPHYLLIN T.
SOMOPHYLLIN-DF vs SOMOPHYLLIN-T
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Theophylline relaxes bronchial smooth muscle by inhibiting phosphodiesterase, increasing intracellular cAMP, and blocking adenosine receptors.
Theophylline is a methylxanthine that inhibits phosphodiesterase, leading to increased intracellular cAMP levels, causing bronchodilation, and also acts as an adenosine receptor antagonist.
Oral: 300-600 mg every 12 hours; extended-release tablets. Titrate to serum theophylline concentration of 5-15 mcg/mL.
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: 3–12 hours in healthy adults; prolonged in hepatic impairment (up to 30 hours), congestive heart failure, and in neonates; also prolonged in elderly and patients with fever or viral illness. Half-life is shorter in smokers (4–5 hours).
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.
Renal excretion of unchanged drug: approximately 10%; hepatic metabolism accounts for >90% of elimination; metabolites are excreted renally. Less than 5% eliminated 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