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Updated: May 31, 2026

Evaluation of Drug Sorption to PVC- and Non-PVC-based Tubes in Administration Sets Using a Pump
Published on: March 11, 2017
Effect of phenobarbital on theophylline disposition
Abstract:
The effect of chronic phenobarbital administration on the pharmacokinetics of theophylline was studied in 6 healthy, nonsmoking adults. Subject compliance was verified by the determination of plasma phenobarbital levels. Following four weeks of phenobarbital administration, all six subjects showed a resultant increase in serum clearance varying from 11% to 60% with a mean increase of 34% (from 3.01 to 4.04 L/hr/1.73 M2). Theophylline appears to be metabolized more rapidly during chronic phenobarbital administration. This effect, therefore, must be taken into account when administering barbiturates to asthmatic patients for whom theophylline therapy is prescribed.
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