Floating drug delivery system

Scientific and technological developments in the research and development of new drug delivery systems have been made in recent years by resolving physiological disorders, such as short gastric residence periods and unpredictable gastric emptying times. Dosage forms that can be hold within the stomach are called as Gastro-retentive Dosage Forms (GRDF). Multiple methods used in the prolongation of gastric residence time are floating drug delivery system, swelling and expanding system, polymeric bio-adhesive system, high density system and other delayed gastric emptying system. Medication-based disease treatment is entering a new era in which a increasing range of innovative drug delivery technologies are being used and are available for clinical use. Floating Drug Delivery Systems (FDDS) is one of the gastro-retentive dosage forms used to achieve extended duration of gastric residency. The aim of writing this review on floating drug delivery systems (FDDS) was to compile the recent literature with particular focus on the main floating mechanism to achieve gastric retention. Sustained oral release of gastrointestinal dosage types provides many benefits for drugs with absorption from the upper sections of the gastrointestinal tract and those that function locally throughout the stomach. This review includes the physiology, factors controlling gastric retention time, excipient variables influencing gastric retention, approaches to designing single-unit, hydro-dynamically balanced system and multi-unit floating structure, and aspects of their classification, formulation and evaluation are discussed in detail, and few applications of these systems.

In the present study, Flurbiprofen was used for preparing Floating dosage form that are designed to retain in stomach for a long time and have developed as a Floating drug delivery system by using various polymers like Carbopol 940 and HPMC K4M to enhance the bioavailability and therapeutic efficacy of Flurbiprofen. The mechanism of action of Flurbiprofen is Non selective COX inhibitor which inhibits the prostaglandin synthesis. Sodium bicarbonate and citric acid was incorporated as a gas generating agent. The direct compression method is used in present work. The formulation was optimized on basis of acceptable tablet properties like optimum hardness, uniform thickness, consistent weight uniformity and low friability. The prepared formulation shows better and significant result all the evaluated parameter. 

The objective of this present study is to formulate and evaluate the floating drug delivery system of Bambuterol HCl prepared by using synthetic polymers. Formulations were prepared by direct compression technique and sodium bicarbonate was incorporated as gas generating agent. Using different polymers of hydroxyl propyl methylcellulose (HPMC) such as, HPMC K100M, HPMC K4M and HPMC K100M for their gel-forming properties. The compressed Bambuterol HCl floating tablets were evaluated for physical parameters like Tablet Thickness, Hardness, % Friability, Weight variation, Content uniformity, In vitro buoyancy, Swelling index and In vitro dissolution study. Its bioavailability was reported about 20%. As the concentration of the polymers in the formulations increased the drug release decreased. Hence it was considered suitable candidate for formulation as gastro-retentive floating drug delivery system. Floating tablets has been accepted as a process to achieve controlled drug delivery by prolonging the residence time of the dosage form at the site of absorption, thereby improving and enhancing the bioavailability of drug.

Verapamil hydrochloride has a short half-life 2.8 to 7.4 hours, a narrow absorption window and is mainly absorbed in proximal areas of GIT. The present investigation aimed to formulate a floating drug delivery system of Verapamil Hydrochloride by Quality by design approach. In risk assessment, the effects of process and formulation variables on particle drug release and floating lag time were investigated. Design of experiments (DoE) and multivariate data analysis were used to identify important process and formulation parameters. A 22 factorial design in replicate was employed to produce controlled release floating tablet. The effect of critical formulation variables i.e. levels of HPMC K15M and gas generating agent (i. e. Sodium bicarbonate and citric acid) on % Drug release after 12 hr (% DRel12) and floating lag time (FLT) were analyzed. Verapamil HCl tablets were evaluated for hardness, friability, weight variation, drug content, floating behavior and drug release studies were conducted in 0.1 N HCl (pH 1.2) at 37 ± 0.5OC. The tablets showed acceptable physicochemical properties. The two independent variables studied exhibited a significant influence (P < 0.05) on % DR 12 Hr and FLT. Numerical and graphical optimization technique employing design space approach was used to develop a new formulation by setting constrains on the dependent and independent variables. The experimental values of % DR 12 Hr and FLT for optimized batch were found to be in close agreement with those predicted by mathematical model. Experimental values obtained from the optimized formulations were in both cases close to the predicted values, thus confirming the validity of the generated mathematical model. These results demonstrated the effectiveness of the proposed floating tablet, as well as the usefulness of the QbD approach for the development of Verapamil floating tablet with optimized properties.

In the recent years, scientific and technological advancements have been made in the research and development of novel drug delivery systems by overcoming physiological troubles such as short gastric residence times and unpredictable gastric emptying times. Several approaches are currently utilized in the prolongation of the gastric residence times, including floating drug delivery systems, swelling and expanding systems, polymeric bioadhesive systems, modified-shape systems, high-density systems and other delayed gastric emptying devices. This review entitled the detailed scenario related to Bilayer floating drug delivery system with their advantages over the conventional drug delivery system and also limitation, which are helpful in development of dosages form. Various types of techniques employed for development of this dosages form. Review focused on formulation aspect of effervescent floating drug delivery system with their evaluation techniques. The purpose of this comprehensive review is to compile the work going on this delivery system. Which provide the valuable information related to formulation aspect to achieve gastric retention and discussed the various factors affect and to overcome it