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

Mark D. Horowitz MD PC

Organization Rheumatology Physician · NPI 1780988717

Mark D. Horowitz MD PC provides Rheumatology Physician services in New York, New York. Registered with an NPI since 2011.

In the registry since
2011
What do these letters mean?
PC — Professional corporation
A form of business registration, not a clinical qualification.

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Practice location Address checks out

21 E 90th St
New York, NY 10128-0654 Not confirmed with CMS for 15 years — call before visiting
Phone: (212) 860-3077
Fax: (212) 410-7410
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Rheumatology Physician (primary) Taxonomy 207RR0500X

Record details

NPI number1780988717
Entity typeOrganization (Type 2)
Organization subpartNo
Authorized official Mark Horowitz — President · (212) 860-3077
NPI enumeratedJanuary 5, 2011
Last updated in NPPESJanuary 5, 2011
Mailing address21 E 90th St, New York, NY 10128-0654

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