Time-dependent influence of pentoxifylline on the pharmacokinetics of orally administered carbamazepine in human subjects.
The time-dependent influence of pentoxifylline (PTX) on the pharmacokinetics of carbamazepine (CBZ) was studied after single-dose oral administration of 100 mg CBZ either alone or in combination with 400 mg PTX at 10:00 and 22:00 h. Serum samples were collected at predetermined time intervals and analysed for unchanged CBZ using high-performance liquid chromatography. The pharmacokinetic parameters of CBZ were calculated using the model-independent method. PTX reduced the rate (Tmax, 8.58 +/- 2.64 vs 5.66 +/- 1.44 h; K(a); 0.47 +/- 0.14 vs 0.72 +/- 0.19 h(-1)), but not the extent of CBZ absorption at 22:00 h treatment. However, such a change was not observed for 10:00 h treatment. No significant changes were observed in other pharmacokinetic parameters of CBZ under the influence of PTX for both 10:00 h as well as 22:00 h treatments. The clinical significance of the time-dependent influence of PTX on the rate of absorption of CBZ will be revealed upon extension of the study to patients.
Poondru
S
S
University College of Pharmaceutical Sciences, Kakatiya University, Warangal 506009, AP, India.
Devaraj
R
R
Boinpally
R R
RR
Yamsani
M R
MR
D000284:Administration, Oral; D000328:Adult; D000927:Anticonvulsants / Q000097:blood / Q000493:pharmacokinetics; D002138:Calibration; D002220:Carbamazepine / Q000097:blood / Q000493:pharmacokinetics*; D004347:Drug Interactions; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D008297:Male; D010431:Pentoxifylline / Q000494:pharmacology*; D013997:Time Factors
D000927:Anticonvulsants; D004791:Enzyme Inhibitors; D002220:Carbamazepine; D010431:Pentoxifylline