Sugai Internal Medicine, located in central Matsuyama City, is a historic medical institution dating back to the Tenpo era (1840) when it served as a clan doctor. In 2024, it celebrated its 100th anniversary, and in 2025, it became the first facility in the Chugoku and Shikoku regions to be certified as a Japan Anti-Aging Medicine Society-designated medical facility. The facility, situated at the foot of Shiroyama with a view of Matsuyama Castle, was designed by Itsuko Hasegawa and offers convenient access from both the Densha-dori and Ropeway Shopping Street areas. In addition to general internal medicine, the clinic specializes in treating sleep disorders including sleep apnea, and also manages lifestyle-related conditions such as hypertension and hyperlipidemia. From an anti-aging medicine perspective, the clinic offers a unique range of examinations to extend healthy lifespan, including glycation testing, genetic testing, brain health checks, and gut flora analysis. Anti-aging measures are also provided through the "Positive Health Checkup" program. In addition to in-house regular health screenings and half-day comprehensive health checkups, the clinic maintains a system that dispatches mobile health screening buses to workplaces throughout the prefecture to support health management. The facility is equipped with high-convenience amenities including English-speaking staff, credit card acceptance, electronic payment, parking, and barrier-free access.