Gastroretentive drug delivery systems a potential approach for antihypertensive drugs: An updated review

Abstract

Oral drug delivery system (DDS) is the preferred route of administration of drugs, but poor bioavailability (BA) of orally administered drugs is still a challenging one, though extensive advancements in drug discovery process are made. Drugs with narrow absorption window in the gastrointestinal tract have poor absorption. Gastric emptying of dosage forms is an extremely variable process and ability to prolong and control the emptying time is a valuable asset for dosage forms, which reside in the stomach for a longer period of time than conventional dosage forms. Therefore, gastroretentive DDSs (GRDDSs) have been developed, which prolong the gastric emptying time. Most of the antihypertensive drugs have short half-life, short gastric residence time, low BA, and narrow absorption window. GRDDS can be a viable option for management of hypertension for several antihypertensive drugs. Several techniques such as floating DDS, low-density systems, raft systems, mucoadhesive systems, high-density systems, super porous hydrogels, and magnetic systems have been employed. These forms are expected to remain buoyant on gastric content without affecting the intrinsic rate of emptying. This results in prolonged gastric retention time of floating forms which improve BA of drug and also improve clinical situations. Prolonged gastric retention not only improves the BA and reduces drug waste but also improves solubility for drugs that are less soluble in a high pH environment. It has applications also for local drug delivery to the stomach and proximal small intestines. Gastroretention helps to provide better availability of new products with new therapeutic possibilities and substantial benefits for patients. Hence, it can be concluded that GRDDS promises to be a potential approach for antihypertensive drugs. This review mainly focuses on the different types of GRDDS used for management of hypertension and also includes the updated compiled study of different antihypertensive drugs explored as GR dosage forms.