Diprophylline (INN) or dyphylline (USAN) (trade names Dilor, Lufyllin) is a xanthine derivative with bronchodilator and vasodilator effects. It is used in the treatment of respiratory disorders like asthma, cardiac dyspnea, and bronchitis. It acts as an a + some more technical info, antagonizing adenosine receptors and inhibiting phosphodiesterase isoenzymes to increase intracellular cyclic AMP in bronchial smooth muscle and pulmonary vasculature, producing bronchodilation, mild positive inotropy and chronotropy, and improved mucociliary clearance. The 7-(2,3-dihydroxypropyl) substitution confers greater aqueous solubility and reduced central nervous system penetration compared with theophylline, which changes pharmacokinetics toward greater renal elimination and generally a more favorable tolerability profile. Standard analytical characterization uses HPLC or LC-MS for assay and impurity profiling, and formulations include oral tablets, syrups, and parenteral preparations where indicated.
Parent: Caffiene/ Pentoxifylline/ Diprophylline/ Dimenhydrinate
Parent: Diprophylline
Parent: Diprophylline/ Theophylline
Typical quality specifications for diprophylline API used in manufacturing and regulatory monographs set assay acceptance around 98.0 percent or greater by validated HPLC, with individual related substances and specified impurities normally limited to the 0.1 to 0.5 percent range depending on the impurity identity and regulatory requirement, and total impurities commonly limited to 0.5 to 1.0 percent. Common related compounds and degradation products to monitor include theophylline and methylxanthine demethylation products, positional isomers of the dihydroxypropyl substituent, and mono-hydroxylated derivatives; manufacturers often set a reporting threshold of 0.05 percent for unspecified impurities and qualification thresholds in line with ICH Q3A/Q3B based on maximum daily dose. Residual solvents must comply with ICH Q3C limits, heavy metals are controlled to typical pharmacopeial ppm levels, and analytical methods for release testing include HPLC-UV and LC-MS for identity, assay, and related-substance quantitation.
Diprophylline is used as a bronchodilator and vasodilator in respiratory conditions such as acute and chronic asthma, bronchitis with bronchospasm, and cardiac dyspnea; it is employed as monotherapy or adjunct therapy to relieve bronchospasm and improve airway patency and diaphragmatic function.
Diprophylline acts primarily by antagonizing adenosine receptors and inhibiting phosphodiesterase enzymes, which raises intracellular cyclic AMP in airway smooth muscle leading to relaxation; additional effects include improved mucociliary clearance, mild cardiac stimulation, and enhanced diaphragmatic contractility, with pharmacokinetic properties influenced by its hydrophilic 7-(2,3-dihydroxypropyl) substituent.
Diprophylline differs from theophylline by the 7-(2,3-dihydroxypropyl) substitution, which increases water solubility and reduces central nervous system penetration; clinically this usually means diprophylline has a more favorable tolerability profile, greater renal elimination and fewer CYP-mediated drug interactions, and generally lower incidence of CNS and gastrointestinal adverse effects, whereas theophylline is more lipophilic, more reliant on hepatic metabolism and often requires closer therapeutic drug monitoring.
