Oral drug delivery is the most preferred way to administer drugs due to its non-invasiveness and patient compliance. One widely used oral drug delivery system is a tablet. When a tablet is ingested, the stomach is the first part of the gastrointestinal tract to come in contact with. However, the main drug absorption site is the duodenum, which follows after the stomach. Gastric emptying rate defines the time taken for the gastric contents to be emptied into the duodenum and therefore is an important determinant of oral drug absorption.

The oral formulations are commonly ingested together with water. In my project, I am investigating how gastric emptying rate of non-caloric liquids (e.g. water) changes in older individuals and how this affects oral drug absorption. The tablet formulation pictured above has been newly developed as a vehicle for the salivary marker caffeine. Caffeine can be used to mark ingested water, providing a non-invasive and patient-friendly way to study changes in gastric emptying in older people. The tablet was produced by direct compression using a tablet press machine with suitable punches and dies, after the raw ingredients had been mixed into a homogeneous powder mixture.