About
Hermes O. P. grew up crossing continents, born in Baghdad to Dutch parents and raised across the Middle East, the Netherlands, England, Nigeria, and the United States before finishing high school in Australia. He became an American citizen in 1984. He completed his undergraduate studies at Trinity University in San Antonio, Texas, then earned his medical degree from the University of Texas Medical Branch in Galveston. A. Medical Center in Phoenix, Arizona.
Dr. Koop holds board certification in Internal Medicine since 1987 and in Critical Care Medicine since 1991. He earned Fellowship in the American College of Physicians in 1992, the same year he moved his family to Naples. At NCH Healthcare System, he served six years as President of the Medical Staff and also chaired both the Department of Medicine and the Credentials Committee. He served on the NCH Board of Trustees from 2009 to 2016 and received the NCH Healthcare Physician of the Year award in 2006. Today he serves as Associate Program Director for the NCH Internal Medicine Residency Program, affiliated with Mayo Clinic School of Medicine and Science. He also holds appointments as Assistant Professor of Internal Medicine at the University of Central Florida College of Medicine and as Adjunct Instructor in Medicine at Mayo Clinic College of Medicine and Science. He is passionate about preventive health, cardiovascular medicine, cancer prevention, and continuity of care across all settings. His wife Joan, a registered nurse, has helped manage the practice for many years. The family enjoys traveling, sailing, and visiting relatives in the Netherlands and Texas.
Education & Training
Undergraduate
Trinity University, San Antonio, Texas
Medical School
University of Texas Medical Branch, Galveston
Residency
Internal Medicine, Good Samaritan Medical Center and V.A. Medical Center, Phoenix, Arizona
Additional Training
Associate Program Director, NCH Internal Medicine Residency Program (affiliated with Mayo Clinic School of Medicine and Science); Assistant Professor of Internal Medicine, University of Central Florida College of Medicine; Adjunct Instructor in Medicine, Mayo Clinic College of Medicine and Science
Certifications
Conditions Treated
Who is Dr. Koop right for?
Dr. Koop is a strong fit for adults who want one physician managing their care across every setting. Patients with chronic conditions such as hypertension, heart disease, diabetes, kidney disease, or arthritis benefit from his breadth of internal medicine training. Those on warfarin find his in-office PT/INR monitoring especially practical. Seasonal Naples residents value his willingness to coordinate care when patients travel. Anyone who places a high priority on direct physician access and preventive health will feel at home in his practice.
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Frequently Asked Questions
Dr. Koop manages a broad range of adult internal medicine conditions. His focus areas include hypertension, heart disease, lung disease, diabetes, kidney disease, cancer care, arthritis, and anticoagulation management. He also emphasizes preventive health and nutrition as part of ongoing care for all his patients.
Yes. Dr. Koop follows his patients into the hospital and does not hand off care to a hospitalist. He also visits patients admitted to rehabilitation facilities and nursing homes. He believes patients recover best under the care of a physician they already know and trust.
Yes, house calls are part of his practice. Home visits fall within the scope of the annual retainer fee, so members do not pay an additional charge for this service.
Dr. Koop's nurse performs a fingerstick protime test in the office. Results come back quickly, allowing Dr. Koop to adjust the warfarin dose before the patient leaves. This in-office PT/INR monitoring keeps anticoagulation management timely and convenient.
Yes. Dr. Koop holds board certification in Internal Medicine since 1987 and in Critical Care Medicine since 1991. He also earned Fellowship in the American College of Physicians in 1992.
Dr. Koop serves as Associate Program Director for the NCH Internal Medicine Residency Program, which affiliates with Mayo Clinic School of Medicine and Science. He also holds an appointment as Assistant Professor of Internal Medicine at the University of Central Florida College of Medicine and serves as Adjunct Instructor in Medicine at Mayo Clinic College of Medicine and Science.
Dr. Koop places prevention at the center of his practice. He focuses on identifying and managing risk factors for cardiovascular disease, cancer, and chronic illness before they progress. Nutrition counseling and routine health screenings play a regular role in his patient visits.
Dr. Koop works closely with four colleagues, Dr. Paul Jones, Dr. George Ferguson, Dr. Ronald Garry, and Dr. Obayed Khan, all of whom run similar private concierge practices. They cover for one another when traveling. Calling Dr. Koop's office while he is away automatically connects patients to the covering physician.
Dr. Koop makes himself directly accessible by telephone 24 hours a day. Members can reach him personally, not an answering service, for urgent concerns. This direct access is a core part of what his concierge practice offers.
Doctor profile last updated June 11, 2026