Precision Beyond Pills: The Era of Implantable Microchips in Controlled Drug Delivery

Controlled drug delivery systems are crucial for maintaining therapeutic efficacy while minimizing side effects. However, they have long presented a significant challenge in the field of medicine. It is difficult to precisely control the drug release kinetics with conventional drug delivery methods, leading to reduced effectiveness and potential toxicity. As a result, there is an increased demand for advanced drug delivery platforms, capable of providing precise and sustained drug release, thereby improving performance and patient outcomes. Implantable microchips are advanced microelectromechanical systems-based devices that have the potential to revolutionize drug delivery and are the preferred choice for researchers and industry pioneers. They are a promising and superior alternative to traditional systems, as they are biocompatible, easy to manufacture, and have patient-friendly designs. Microchips are designed to provide precise control over both the rate and timing of drug release. A single microchip can be engineered with multiple reservoirs (loaded with different active moieties) via different microfabrication techniques, enabling multi-drug therapy. Currently, most implantable microchips are designed as single-use devices, intended to be removed or replaced once the drug reservoirs are depleted. Nevertheless, research is ongoing to address this issue, and efforts are being made to design refillable microchips. They have a wide range of applications, including chronic disease management for conditions like diabetes and cardiovascular diseases, cancer therapy, and treatment of neurological disorders like Parkinson's disease. The current review offers a comprehensive exploration of the evolution of implantable microchips for drug delivery, tracing their development from inception to the latest advancements along with their working methods and fabrication technologies.