Vol. 2, Issue 1, Part A (2020)

Controlled release of dosage forms has a non-uniform absorption profile, insufficient drug release and shorter residence time due to variation in gastric emptying. These dosage forms encounter several physiological constraints such as the inability to retain and locate the controlled drug delivery system within the desired region of the gastrointestinal tract. These considerations led to the development of oral controlled release dosage forms with gastro-retentive properties. Hollow microspheres are one of the gastro-retentive drug delivery systems based on the non‑effervescent approach. They are spherical empty particles without core and can remain in the gastric region for prolonged periods. They hold promise as one of the potential approaches for gastric retention. They can extend the gastric residence time of drugs significantly and help in improving the bioavailability. This review attempts to provide insight into the basics of hollow microspheres, recent advances and future potential of this drug delivery system.