Comparative Pharmacology
Head-to-head clinical analysis: SOMOPHYLLIN CRT versus THEOPHYL SR.
Peer-Reviewed Evidence
Head-to-head clinical analysis: SOMOPHYLLIN CRT versus THEOPHYL SR.
SOMOPHYLLIN-CRT vs THEOPHYL-SR
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Theophylline acts as a bronchodilator via nonselective phosphodiesterase inhibition, increasing intracellular cAMP levels. It also antagonizes adenosine receptors and may have anti-inflammatory effects.
Theophylline is a methylxanthine that inhibits phosphodiesterase, increasing cyclic AMP levels, and antagonizes adenosine receptors, leading to bronchodilation and anti-inflammatory effects.
Theophylline 400 mg orally once daily (24-hour extended-release). Titrate based on serum theophylline levels; target trough 5-15 mcg/mL.
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: 8-10 hours in adults (non-smokers); prolonged to 12-16 hours in elderly or hepatic impairment; reduced to 4-6 hours in smokers (CYP1A2 induction).
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.
Primarily hepatic metabolism (90%) via CYP1A2 and CYP3A4; renal excretion of unchanged drug accounts for ~10% in adults, with minor biliary/fecal elimination (<1%).
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