Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.
NPIDirectory

Dr. Mark David Horowitz, MD

Individual provider Internal Medicine Physician · NPI 1154490530

Dr. Mark David Horowitz, MD is an Internal Medicine in New York, New York. Graduated from Northeastern Ohio University College of Medicine in 1983, 43 years ago. Accepts Medicare assignment. Licensed in New York.

Years since qualifying
43
Trained at
Northeastern Ohio University College of Medicine
Licensed in
NY
In the registry since
2006
Specialties on file
2
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

See every abbreviation used in this directory →

Claim this listing Report a problem Suggest an edit

Practice location Address checks out

21 E 90th St
New York, NY 10128
Phone: (212) 860-3077
Fax: (212) 410-7410
Show map & directions

Directions in Google Maps · Apple Maps · OpenStreetMap

Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Internal Medicine Physician (primary) Taxonomy 207R00000X · Licence 1613581 (NY)
Rheumatology Physician Taxonomy 207RR0500X · Licence 1613581 (NY)

Record details

NPI number1154490530
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedNovember 7, 2006
Last updated in NPPESSeptember 11, 2025

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyINTERNAL MEDICINE
Also practisesRHEUMATOLOGY
Medical schoolNORTHEASTERN OHIO UNIVERSITY COLLEGE OF MEDICINE
Graduated 1983 (43 years in practice)
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

Other providers in New York