SUMMARY
Ofloxacin (OFX) is a synthetic broad spectrum analog of second generation fluoroquinolone antibiotic. It is used for the treatment of urinary tract, prostate, skin, urinary and respiratory tract infections. Ornidazole (ORN) is a nitroimidazole derivative. It is used in the treatment of bacterial vaginosis, trichomoniasis, amoebiasis, giardiasis and infections due to anaerobic bacteria. These drugs are highly soluble in acidic media and precipitates in alkaline media thereby losing its solubility. Hence we attempted to develop a gastro retentive floating matrix type drug delivery system for Ofloxacin and Ornidazole in combined dosage form with hydroxyl propyl methyl cellulose (HPMC) K15M, HPMC K100M and polyethylene oxide 18NF (PEO). The physicochemical compatibility of the drug and the polymers was studied by infrared spectroscopy and differential scanning calorimetry. The results suggested no physicochemical incompatibility between the drug and the polymers. The prepared floating drug delivery systems were evaluated for physicochemical characteristics, mainly in vitro release and in vivo residence time by radiographic studies. The best formulation (F2) was selected based on in vitro release and physicochemical characteristics and used in vivo radiographic studies by incorporating BaSO4. These studies revealed that tablets 300 ± 30 minutes in healthy human volunteers in fasting state and indicated that the gastric retention was increased by floating principle. By fitting the data into zero order, first order and Higuchi models, it was concluded that drug release from matrix tablets followed Higuchi model and the mechanism of drug release was diffusion mediated. Based on the physical evaluation, in vitro drug release and in vivo characteristics, it was concluded that for potential therapeutic use, suitable for the development of a floating drug delivery system of Ofloxacin and Ornidazole in combined dosage form.