%0 Journal Article %T Statistical optimization of a novel excipient (CMEC) based gastro retentive floating tablets of propranolol HCl and it¡¯s in vivo buoyancy characterization in healthy human volunteers %A Venkata Meka %A Sreenivasa Nali %A Ambedkar Songa %A Janaki Battu %A Venkata Ramana Kolapalli %J DARU Journal of Pharmaceutical Sciences %D 2012 %I BioMed Central %R 10.1186/2008-2231-20-21 %X Drug delivery systems (DDS) are used for maximizing the therapeutic index of the drug and also targeted for reduction in the side effects. All over delivery systems the oral drug delivery has become the mainstay of treatment due to higher patient compliance and reduced patient discomfort. Under certain circumstances prolonging the gastric retention of a DDS is desirable for achieving greater therapeutic benefit of the drug [1]. For example, drugs that are absorbed in the proximal part of the gastrointestinal tract (GIT), and the drugs that are less soluble or are degraded by the alkaline pH may benefit from prolong gastric retention. In addition, for local and sustained drug delivery to the stomach and the proximal small intestine to treat certain conditions, prolonging gastric retention of the therapeutic moiety may offer numerous advantages including improved bioavailability, therapeutic efficacy and possible reduction of the dose size [2-4]. All over the retentive systems gastric floating system for modulation of oral controlled drug delivery was found to be great importance. Hence in the present investigation effervescent floating systems were developed for prolonging the gastric retention.In the present investigation propranolol HCl was selected as a model drug for the development of gastro retentive floating drug delivery systems (GRFDDS). Propranolol is a nonselective beta-adrenergic receptor blocking agent possessing no other autonomic nervous system activity used for the treatment of hypertension [5]. It is highly lipophilic and almost completely absorbed after oral administration. However, it undergoes high first-pass metabolism by the liver and on average, only about 25% of propranolol reaches the systemic circulation [6]. Variability of propranolol bioavailability is depends upon the secretory transporter P-glycoprotein (P-gp) located on the epithelium cells. Although P-gp appears to be distributed throughout the GIT, its levels are higher in more distal %K Propranolol HCl %K Gastro retentive %K Floating %K Central composite %K Carboxymethyl ethyl cellulose %U http://www.darujps.com/content/20/1/21