Background: Oral administration of medications and current oral modified-release systems are the most preferred drug delivery routes, but they provide efficacy up to 12-24 hours per administration and are not useful when the patient has short transit time. The once-daily administered formulations are the endpoint of many types of drug development, and some innovations in capsule endoscopy (CE) can solve this problem.
Objective: This review aims to reveal recent advances in drug delivery systems (DDS) for CE as an essential field of research for more precise drug targeting at the gastrointestinal (GI) tract. Methods: We performed a narrative overview of the MEDLINE database from 1991-2020 using the keywords of DDS and CE with synthesizing the findings, hand searches, and authoritative articles. Results: There are microelectromechanical systems and non-mechanical patent technologies for DDS for CE, and the implementation of wireless-capsule medical devices into the human body will provide new diagnostic and therapeutic options. Integrating biomedical CE with DDS and the cloud technology will bring remote real-time feedbackbased automated treatment or responsive medication. Conclusion: Swallowable drug delivery systems for capsule endoscopy brings an entirely new approach for diagnostic and therapeutic methods in digestive diseases.Keywords: Capsule endoscopy, therapeutic capsule, drug delivery systems, release mechanism, wireless capsule robots, electronic pill.