The application of IT technology to medicine accelerates the improvement of medical quality, the development of diagnostic modality, and the application of precision medicine. The nicotine dependence treatment app & CO checker were approved as the first program medical device in Japan. A new category of medical care, digital therapy, is about to begin. Apps used for digital treatment are commonly referred to as digital medicine. Many of these apps are related to cognitive behavioral therapy and are also called behavior modification apps. US venture companies are leading the development of digital medicine. Japanese pharmaceutical companies and venture companies are following them. Since the approval of new digital drugs will be subject to examination by the Pharmaceuticals and Medical Devices Agency (PMDA), a new program medical device examination department has been established in PMDA to strengthen the examination system. In the future, it is expected that the development of digital drugs will progress and many products will be used in clinical practice. However, there are many issues to be resolved, such as the mechanism of action and the interaction between drugs and digital medicine. The pharmacology research on the analysis of the effects of digital drugs will progress in future.