Comparative Pharmacology
Head-to-head clinical analysis: ELIXOPHYLLIN versus SLO PHYLLIN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ELIXOPHYLLIN versus SLO PHYLLIN.
ELIXOPHYLLIN vs SLO-PHYLLIN
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.
SLO-PHYLLIN (theophylline) is a xanthine bronchodilator that relaxes bronchial smooth muscle, likely by inhibiting phosphodiesterase, increasing intracellular cAMP, blocking adenosine receptors, and enhancing endogenous catecholamine release.
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.
Theophylline (Slo-Phyllin) immediate-release: 100-200 mg orally every 6 hours; sustained-release: 200-400 mg orally every 12 hours. Dose titrated 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 is approximately 3-8 hours in adults (non-smokers, healthy), 1-5 hours in smokers, and 20-30 hours in neonates. Clinical context: Half-life is prolonged in hepatic cirrhosis, heart failure, and with certain drug interactions (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: ~10% unchanged; hepatic metabolism accounts for ~90% of elimination, with metabolites excreted in urine. Fecal: <5%.
Category C
Category C
Xanthine Bronchodilator
Xanthine Bronchodilator