Comparative Pharmacology
Head-to-head clinical analysis: ELIXOPHYLLIN versus PHYLLOCONTIN.
Head-to-head clinical analysis: ELIXOPHYLLIN versus PHYLLOCONTIN.
ELIXOPHYLLIN vs PHYLLOCONTIN
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.
Sustained-release theophylline; nonselective phosphodiesterase (PDE) inhibitor, adenosine receptor antagonist, and histone deacetylase activator. Bronchodilation via relaxation of bronchial smooth muscle; also reduces airway hyperresponsiveness and inflammation.
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.
For chronic obstructive pulmonary disease and asthma: initial dose 225 mg orally twice daily; may increase to 450 mg twice daily. Based on theophylline, target serum concentration 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: 3-8 hours in non-smoking adults; reduced to 1.5-5 hours in smokers; prolonged to 10-30 hours in heart failure or hepatic cirrhosis.
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: approximately 10% unchanged; hepatic metabolism accounts for ~90% of clearance; metabolites eliminated renally.
Category C
Category C
Xanthine Bronchodilator
Xanthine Bronchodilator