Formulation and evaluation of modified-release effervescent floating tablets of ofloxacin

Abstract

Aims: Ofloxacin is used as anti-microbial agent. Due to its high solubility in gastric pH, a floating drug delivery system was selected to improve the bioavailability and therapeutic efficacy of the drug. Settings and Design: The purpose of the study was to prepare and evaluate effervescent floating tablets of ofloxacin to prolong its gastric residence and increase bioavailability. Materials and Methods: Drug, semi-synthetic and natural polymers, such as HPMC K4M, Guar gum, Xanthan gum and Chitosan, were used. Sodium bicarbonate and citric acid were used as gas-generating agents and tablet compression was done by direct compression. The prepared tablets were characterized and were evaluated for in vitro floating behavior, swelling index, in vitro drug release studies and release kinetics. Results: Formulation F6 containing xanthan gum and chitosan in a 1:1 ratio attained sustained release for 12 h and drug release observed was about 76.7%. Swelling index was in the range 62.17 ± 1.49% to 194.02 ± 1.05%. Floating lag time was observed in the range 4.11-6.26 min. Conclusion: The in vitro results showed better drug release conditions, supported by follow-up in vivo studies, suggesting that this formulation is advantageous over the current marketed formulation, through increased gastric residence and bioavailability.