Comparative Pharmacology
Head-to-head clinical analysis: ELIXOPHYLLIN versus SLO BID.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ELIXOPHYLLIN versus SLO BID.
ELIXOPHYLLIN vs SLO-BID
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Inhibits phosphodiesterase, increasing intracellular cAMP, leading to bronchodilation and anti-inflammatory effects.
Relaxes smooth muscle of bronchial airways and pulmonary blood vessels by inhibiting phosphodiesterase, increasing intracellular cAMP, and promoting bronchodilation.
Theophylline (Elixophyllin) immediate-release: Initial dose 300 mg/day PO divided every 6-8 hours; titrate based on serum theophylline concentration (target 5-15 mcg/mL). Typical adult dose 400-600 mg/day PO divided every 6-8 hours. Sustained-release: 400-600 mg/day PO every 12 hours.
Dose: 300-600 mg orally every 12 hours. Immediate-release: 5 mg/kg loading dose then 3 mg/kg every 6 hours. Extended-release: 10-15 mg/kg/day divided every 12 hours. Titrate to serum theophylline concentration of 5-15 mcg/mL.
None Documented
None Documented
Terminal elimination half-life in adults is approximately 7-9 hours (range 3-12 hours) for non-smokers, and 4-5 hours for smokers. In children (1-9 years), half-life averages 3-4 hours; in neonates, it is prolonged (20-30 hours). Clinical context: Half-life may be increased in hepatic impairment, congestive heart failure, and with concurrent administration of drugs that inhibit CYP1A2 and CYP3A4 (e.g., cimetidine, erythromycin, ciprofloxacin). Decreased half-life occurs with enzyme inducers (e.g., phenytoin, carbamazepine, rifampin, smoking).
Terminal elimination half-life: 3-15 hours (mean ~10 hours in adults; 20-30 hours in neonates; 1-5 hours in smokers). Clinically, half-life decreases with smoking, increases with hepatic disease, heart failure, and certain drugs (e.g., cimetidine, ciprofloxacin).
Theophylline is primarily eliminated by hepatic metabolism (approximately 90%), with less than 10% excreted unchanged in urine. Renal excretion of unchanged drug accounts for about 10% in adults, but in neonates and infants, it may be higher (up to 50%). Fecal excretion is negligible (<1%).
Renal: 90% as metabolites (caffeine, theobromine, paraxanthine, and unchanged drug; 1,3-dimethyluric acid, 1-methyluric acid, and 3-methylxanthine). Biliary/fecal: <10%.
Category C
Category C
Xanthine Bronchodilator
Xanthine Bronchodilator