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MARK C. NITZBERG, P.C.
NPI 1992900013
Internal Medicine - Gastroenterology in Methuen, MA

Active since June 19, 2007
380 R MERRIMACK ST., STE. 2C, METHUEN, MA 01844(978) 681-1977(978) 686-8918 Get Directions Write a Review

NPPES record last updated: November 15, 2017. Verified against the NPPES registry weekly; last sync: November 01, 2026.

About Mark C. Nitzberg, P.c. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

MARK C. NITZBERG, P.C. (NPI 1992900013) is a healthcare organization registered as a gastroenterology in Methuen, Massachusetts and active in the NPI registry since June 2007. The organization maintains a secondary practice location in Methuen and lists Mark C. Nitzberg, President, as its authorized official.

NPPES Registry Identity

NPI1992900013
Entity TypeOrganization
Primary Taxonomy207RG0100X
Legal Business NameMARK C. NITZBERG, P.C.
Location Address380 R MERRIMACK ST., STE. 2CMethuen, MA 01844
Mailing Address380 R Merrimack St., Ste. 2cMethuen, MA 01844 · (978) 681-1977 · Fax (978) 686-8918
Phone(978) 681-1977
Fax(978) 686-8918
Organization SubpartNo
Authorized OfficialMark C. NitzbergPresident · (978) 681-1977
Enumeration DateJune 19, 2007
Last NPPES UpdateNovember 15, 2017
✔ NPI 1992900013 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyInternal Medicine · GastroenterologyAllopathic & Osteopathic Physicians
Taxonomy Code207RG0100X
License✔ Licensed in MA · 74584
Definition
An internist who specializes in diagnosis and treatment of diseases of the digestive organs including the stomach, bowels, liver and gallbladder. This specialist treats conditions such as abdominal pain, ulcers, diarrhea, cancer and jaundice and performs complex diagnostic and therapeutic procedures using endoscopes to visualize internal organs.
Also ListedInternal MedicineTaxonomy 207R00000X · License 74584 (MA)
380 R MERRIMACK ST., Methuen, MA 01844
Open in Google Maps ↗

Secondary Practice Location 1

Location 1411 Merrimack St, Suite 202Methuen, MA 01844-5821 · Phone (978) 681-1977 · Fax (978) 686-8918

Other Identifiers 3

Medicare UPINF45853MA
Medicaid9781480MA
Medicare ID-Type UnspecifiedM21709MA · Group

Group Practice 1

Group TaxonomyThis provider is a business group of one or more individual practitioners, who practice with different areas of specialization.193200000X MULTI-SPECIALTY GROUP

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Anthem Blue Cross and Blue Shield.Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment and the clinicians who bill Medicare through this organization, from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Mark C. Nitzberg, P.c. is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Clinicians Billing Medicare Through This Organization

Medicare enrollment records show 1 clinician reassigns Medicare billing to Mark C. Nitzberg, P.C., which bills Medicare for the services this clinician delivers.

Clinician (1)

Mark Nitzberg, M.D.
Gastroenterology
NPI 1881652758
38R MERRIMACK ST. SUITE 2C
Methuen, MA 01844
(978) 681-1977
✔ PECOS✔ Accepts Medicare1.7 mi

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Mark C. Nitzberg, P.C.'s NPI number?

The NPI number for Mark C. Nitzberg, P.C. is 1992900013. It was assigned to this organization in the NPPES registry on June 19, 2007.

Where is Mark C. Nitzberg, P.C. located?

Mark C. Nitzberg, P.C. is located at 380 R Merrimack St. Ste. 2C, Methuen, MA 01844. The listed phone number is (978) 681-1977.

What is Mark C. Nitzberg, P.C.'s specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Gastroenterology, with taxonomy code 207RG0100X.

Is Mark C. Nitzberg, P.C. enrolled in Medicare?

Yes. Mark C. Nitzberg, P.C. is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Mark C. Nitzberg, P.C.?

According to the CMS Revalidation Reassignment List (October 2026 release), 1 clinician (Gastroenterology) reassigns their Medicare billing to Mark C. Nitzberg, P.C.. A reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for the clinician's services. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

What insurance does Mark C. Nitzberg, P.C. accept?

Health plans from Anthem Blue Cross and Blue Shield list Mark C. Nitzberg, P.C. as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

When was this NPI record last updated?

The NPPES record for Mark C. Nitzberg, P.C. was last updated on November 15, 2017. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 8 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.