Comparative Pharmacology
Head-to-head clinical analysis: PHYLLOCONTIN versus QUIBRON T SR.
Peer-Reviewed Evidence
Head-to-head clinical analysis: PHYLLOCONTIN versus QUIBRON T SR.
PHYLLOCONTIN vs QUIBRON-T/SR
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
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 is a methylxanthine that relaxes bronchial smooth muscle by inhibiting phosphodiesterase, increasing intracellular cAMP, and antagonizing adenosine receptors.
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.
200-400 mg orally every 12 hours; extended-release tablets. Initial dose 200 mg every 12 hours; may increase by 200 mg daily every 3-7 days based on serum theophylline levels (target 5-15 mcg/mL). Maximum 800 mg/day.
None Documented
None Documented
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.
Terminal t1/2: 3-12 hours (adults); 1-9 hours (children); prolonged in cirrhosis (up to 30 hours), heart failure, elderly. Clinical context: Narrow therapeutic index (5-15 mcg/mL); dosing interval adjusted based on t1/2.
Renal: approximately 10% unchanged; hepatic metabolism accounts for ~90% of clearance; metabolites eliminated renally.
Renal: ~10% unchanged; Hepatic metabolism (CYP1A2, CYP3A4): 90% to inactive metabolites (1,3-dimethyluric acid, 3-methylxanthine, 1-methyluric acid). Biliary/fecal: minimal (<5%).
Category C
Category C
Xanthine Bronchodilator
Xanthine Bronchodilator