Comparative Pharmacology
Head-to-head clinical analysis: SOMOPHYLLIN DF versus THEO 24.
Peer-Reviewed Evidence
Head-to-head clinical analysis: SOMOPHYLLIN DF versus THEO 24.
SOMOPHYLLIN-DF vs THEO-24
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Theophylline relaxes bronchial smooth muscle by inhibiting phosphodiesterase, increasing intracellular cAMP, and blocking adenosine receptors.
Theophylline, a xanthine derivative, acts as a non-selective phosphodiesterase (PDE) inhibitor (primarily PDE3 and PDE4), increasing intracellular cAMP and cGMP in airway smooth muscle and inflammatory cells. It also antagonizes adenosine receptors (A1, A2), stimulates endogenous catecholamine release, and may enhance histone deacetylase activity, reducing inflammation.
Oral: 300-600 mg every 12 hours; extended-release tablets. Titrate to serum theophylline concentration of 5-15 mcg/mL.
300-600 mg orally once daily, extended-release capsule; individualize based on serum theophylline concentration targeting 5-15 mcg/mL.
None Documented
None Documented
Terminal elimination half-life: 3–12 hours in healthy adults; prolonged in hepatic impairment (up to 30 hours), congestive heart failure, and in neonates; also prolonged in elderly and patients with fever or viral illness. Half-life is shorter in smokers (4–5 hours).
Terminal elimination half-life is approximately 3–8 hours in adults (non-smokers), 4–5 hours in smokers (due to enzyme induction), and highly variable in neonates (24–36 hours) and children (1–9 hours). Half-life is prolonged in cirrhosis (up to 30 hours), heart failure, and with concomitant medications (e.g., cimetidine, erythromycin).
Renal excretion of unchanged drug: approximately 10%; hepatic metabolism accounts for >90% of elimination; metabolites are excreted renally. Less than 5% eliminated in feces.
Approximately 90% of theophylline is eliminated hepatically via metabolism (principally CYP1A2 and CYP3A4), with less than 10% excreted unchanged in urine. Renal excretion of unchanged drug is minimal (about 5%) in adults. Biliary/fecal excretion accounts for less than 1%.
Category C
Category C
Bronchodilator
Bronchodilator