A pharmacokinetic study of the recommended dosing schedules of Theo-Dur and Uniphylline

Theo-Dur, 300 mg twice daily, and Uniphylline, 600 mg once daily taken with food were compared in an open cross-over study in healthy volunteers. Uniphylline had significantly (P less than 0.001) higher peaks, lower troughs and wider variation in theophylline concentrations than Theo-Dur. Peak plasma concentrations were reached earlier for Theo-Dur but the difference failed to reach statistical significance (0.05 less than P less than 0.1). There was no significant difference between the two drugs in area under the plasma concentration time curve. Therapeutic occupancy lasted significantly longer (P less than 0.05) with Theo-Dur; eight volunteers attained 24 h therapeutic occupancy after administration of Theo-Dur compared to 4 h with Uniphylline.