Bio-pharmaceutical evaluation of tenoxicam suppositories

With the object of reducing hepatic first-pass elimination of tenoxicam, the drug was formulated in suppository form using different suppository bases. The bases used include Witepsols, Suppocires, Novatas in addition to PEGs an cacao butter. The effect of different additives, surfactants and gels, on drug suppository formulation in Witepsol H15 was also investigated. Suppositories containing tenoxicam solid dispersions were also evaluated, using PEG 4000 and 6000, PVP K25, the hydrotropes sodium benzoate and sodium salicylate, urea, lactose, sorbitol, mannitol, and the electrolytes sodium chloride, magnesium carbonate and aluminum hydroxide. The suppositories prepared were evaluated for in vitro drug release, when fresh and on storage. Selected formulae were also evaluated through tenoxicam relative bioavailability and its anti-inflammatory activity compared to indomethacin as reference drug

Formulation and evaluation of tenoxicam capsules

With the aim of preparing tenoxicam capsules, different additives commonly used in capsule formulation were used for the preparation of tenoxicam capsules. Twenty-four different capsule formulae were prepared and were subjected to an in vitro dissolution study using the USP dissolution tester. The anti-inflammatory activity was determined using the rat paw edema technique taking indomethacin as a standard for comparison. The study revealed that there was a significant difference between indomethacin and tenoxicam from its capsule formulations indicating the superior anti-inflammatory activity of tenoxicam. The bioavailability of tenoxicam was determined using an HPLC assay, where the pharmacokinetic parameters were determined using rabbits plasma. A good correlation was found between the percentage inhibition in edema activity and the peak plasma concentration as a measure of drug absorption where the correlation coefficient was found to be 0.928