Yotsuya Thyroid Diabetes Clinic is located in Yotsuya 1-chome, Shinjuku-ku, Tokyo, specializing in thyroid and diabetes care. The clinic provides internal medicine services with specialized treatment for thyroid disorders and diabetes. Appointments are available weekday mornings, Monday and Thursday evenings, and Saturday mornings. On the 1st, 3rd, and 5th Saturdays, Dr. Ono provides care, while Dr. Taniyama treats patients on the 2nd and 4th Saturdays. The clinic performs fine needle aspiration (FNA) on specific days and offers influenza vaccinations. The facility is barrier-free and provides English-language support. Following relocation and renaming from Samon-cho, Shinjuku-ku, the clinic continues to enhance its medical services.