ABSTRACT
<p><b>OBJECTIVE</b>To establish an high-performance liquid chromatography (HPLC)-based method for analysis of the pharmacokinetics and relative bioavailability of dextromethorphan chewing gum tablets in rabbits.</p><p><b>METHODS</b>The pharmacokinetic parameters and the relative bioavailability of dextromethorphan chewing gum preparation in rabbits were compared with those of the commercially available chewing dextromethorphan tablets using 3P97 software.</p><p><b>RESULTS</b>Pharmacokinetic analysis of the new dextromethorphan chewing gum tablets showed a AUC of 488.76 ∓ 175.00 ng.ml(-1).h, C(max) of 95.45 ∓ 17.53 ng/ml, and t(max) of 1.83 ∓ 0.57 h as compared with the corresponding parameters of 370.13 ∓ 90.56 ng.ml(-1).h, 174.00 ∓ 47.88 ng.ml, and 1.04 ∓ 0.14 h for the commercially available chewing tablets. The relative bioavailability of the new chewing gum medicine system was (140.73 ∓ 65.91)%.</p><p><b>CONCLUSION</b>The new dextromethorphan chewing gum preparation shows an increased AUC((0→)), decreased C(max), and prolonged t(max) in comparison with the commercially available chewing tablets, with also a greatly enhanced relative bioavailability.</p>