Preparation, evaluation and pharmacokinetics of diosmin herbosome in beagle dogs

Diosmin is one of the most widely used phlebotonic drugs, but its poor bioavailability has restricted its usage. The aim of this study was to formulate a complex Diosmin with phospholipids (75% in PC, in 1:2 molar ratios) and to evaluate for solubility, drug content, X-ray diffraction (XRD), differential scanning calorimetry (DSC) and in vitro dissolution study. Further to test the bioavailability of both the complex and Alvenor® in beagle dogs and compare pharmacokinetic parameters. Diosmin herbosome was found to be more soluble than both pure diosmin and Alvenor® . The complex contained 71.94% drug content. DSC thermograms and XRD also proved the claim of the complexation. The dissolution profile of diosmin herbosome and Alvenor® in water-ethanol medium showed an increase of the dissolution for diosmin herbosome. Comparison of plasma concentration and main pharmacokinetic parameters of diosmin herbosome treated and Alvenor® treated dogs showed a higher Cmax for the complex with longer elimination half-life. The complexation of diosmin with phospholipids can be potentially used in enhancing the absorption and solubility, consequently increasing the bioavailability of the drug.