• Journal of Pharmaceutical Investigation
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• v.21 no.2
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• pp.103-110
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• 1991

Two new prodrugs of lonazolac, lonazolac acetic acid ester and lonazolac argininate, were prepared and examined for physicochemical properties and biopharmaceutical characteristics. The prodrugs were stable in solid state and lonazolac argininate showed higher dissolution rate than lonazolacca in both artificial gastric and intestinal juices. These prodrugs have higher analgegic effect than that of lonazolac-Ca in mice, and increased anti-inflammatory activities in rats. In addition, ulcerogenic effects and acute toxicity of these prodrugs were lower than those of lonaaolac-Ca. Lonazolac acetic acid ester showed larger area under the plasma concentration-time curves (AUC) than that of lonazolac. Therefore, it was suggested that these prodrugs of lonazolac have advantages over lonzolac-Ca for not only enhanced bioavailability but also decreased ulcerogenic and toxic effects.

• Archives of Pharmacal Research
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• v.12 no.2
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• pp.108-113
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• 1989

A new column-switching high performance liquid chromatographic method was developed for the determination of lonazolac in plasma. This method was based on the on-line trace enrichment of lonazolac using a precolumn packed with Amberlite XAD-2. The analysis was complete in 20 min. between injections and the limit of detection was $0.1{\mu}g/ml$ using $100{\mu}l$ of plasma. The method was linear in range of $0.1-10{\mu}g/ml$ with a correlation coefficient of 0.9991. Absolute recovery of lonazolac from the spiked plasma samples ranged from 95.6% to 97.1%. The method was shown to be reproducible over the concentration range studied.