Toyoki Naika, located in Isobe, Chikuma City, Nagano Prefecture, is an internal medicine specialty clinic operated by Medical Corporation Hoyokai. Director Dr. Takaaki Toyoki holds a medical doctorate from Teikyo University School of Medicine and is an experienced physician with certifications in internal medicine, cardiology, and as a certified industrial physician. Vice Director Dr. Daigo Toyoki also holds a medical doctorate and specializes in nephrology, establishing a well-rounded team of specialists. The clinic promptly introduces state-of-the-art diagnostic equipment, emphasizing rapid and thorough diagnoses. The clinic offers various vaccinations including influenza, pneumococcal, measles-rubella, varicella, mumps, and hepatitis A and B, all properly stored in dedicated refrigerators. The clinic also accepts specific health checkups for Chikuma City and Sakaki Town, serving as a community health management hub. To prevent hospital-acquired infections, infectious disease patients are seen by appointment. With parking facilities and barrier-free design, the clinic provides easy access for elderly patients and those arriving by car. Starting in May 2026, a dermatology department will be added, and the clinic will expand its services as 'Toyoki Naika Hifuka Clinic.'