Formulation and evaluation of floating dosage forms: An overview

Floating dosage forms are emerging as a promising novel dosage forms. Floating dosage forms can be prepared as tablets, capsules by incorporating suitable excipients as well by adding certain gas-generating agents, which in turn give the buoyancy to the dosage form in gastrointestinal fluids. The various excipients such as poloxamer 188, carbopol 934P, hydroxypropylmethylcellulose, polyethylene glycol 6000, beta-cyclodextrin, polyvinyl acetate, purified shellac, Eudragit RS, or polymethyl methacrylate, alginate beads and casein-gelatin beads in combination provide buoyancy to the dosage form. The degree of drug embedded in dosage form determines its release. The hydrated layer slowly releases the drug from the dosage form by diffusion. Due to the hydrated gel layer, floating dosage forms can remain afloat in stomach for 6-8 h and release the active pharmaceutical ingredients for extended period of time in gastric environment. These systems have more flexibility in dosage design than conventional dosage form. For the optimization of the drug release pattern in vivo, floating devices such as InteliSite capsule can be used as it provides noninvasive determination of drug absorption and bioavailability at specific sites by gamma scintigraphy. This review summarizes various techniques adopted in the development of floating dosage forms, in vitro and in vivo studies to evaluate the performance and application of floating dosage forms. [PUBLICATION ABSTRACT]