Matthew R Mannini, DO is a board-certified physician, specializing in Internal medicine. With an office conveniently located in Brewster, NY, Dr. Mannini can help with your everyday health needs, from regular checkups to caring for you when you're injured or ill. An Optum, primary care physicians can oversee all your health care needs. We care for short-term health problems like the common cold or a sprained ankle. Or, long-term health problems, such as allergies, high blood pressure, heart disease and diabetes. Our doctors will work with specialists to make sure you get any extra care you might need. Optum accepts most major health plans.