A medical license is required for a doctor to practice medicine in a particular state. Requirements vary by state but most require, at a minimum, post-graduate training in the doctor’s specific specialty. An NPI number is a national identifier unique to an individual health care provider and is managed by the Center for Medicare & Medicaid Services (CMS).
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The overall average patient rating of Dr. Dennis O'Brien is Good.
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Specialties & Research
Dr. Dennis O'Brien, MD is board certified in Internal Medicine.
Education & Awards
Dr. O'Brien graduated from Universite De Bordeaux Ii.
Dr. O'Brien has 1 hospital affiliations:
- St Catherine Of Siena Medical Center
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- Additional Information
- Dr. Dennis Sean O'Brien MD is a male Internist, has 31 years of experience and practices in Internal Medicine.
- Where does Dr. Dennis S. O'Brien practice?
- Dr. Dennis O'Brien has 4 office locations.
Dr. Dennis O'Brien practices Internal Medicine near Saint James, NY.
Additional practice locations include: Smithtown, NY.
See Saint James Internists.