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MARK C. NITZBERG M.D.
NPI 1881652758
Internal Medicine - Gastroenterology in Methuen, MA

Active since May 02, 2006PECOS EnrolledAccepts Medicare Assignment
38R MERRIMACK ST., SUITE 2C, METHUEN, MA 01844(978) 681-1977(978) 686-8918 Get Directions Write a Review

NPPES record last updated: November 16, 2017. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Mark C. Nitzberg M.d. NPPES

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

MARK C. NITZBERG M.D. (NPI 1881652758) is an individual gastroenterology provider in Methuen, Massachusetts, licensed in Massachusetts (74584) and active in the NPI registry since May 2006. He is enrolled in Medicare PECOS, is affiliated with Lawrence General Hospital, and is a graduate of University Of Massachusetts Medical School (1989).

NPPES Registry Identity

NPI1881652758
Entity TypeIndividualMale
Primary Taxonomy207RG0100X
Provider Legal NameMARK C. NITZBERGCredential: M.D.
Location Address38R MERRIMACK ST., SUITE 2CMethuen, MA 01844
Mailing Address380r Merrimack St., Suite 2cMethuen, MA 01844 · (978) 681-1977 · Fax (978) 686-8918
Phone(978) 681-1977
Fax(978) 686-8918
Sole ProprietorYes
Medical School CMSUniversity Of Massachusetts Medical SchoolGraduated 1989
Enumeration DateMay 2, 2006
Last NPPES UpdateNovember 16, 2017
✔ NPI 1881652758 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ 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.
38R MERRIMACK ST., Methuen, MA 01844
Open in Google Maps ↗

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, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Mark C. Nitzberg M.d. is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID3870520588
PECOS Enrollment IDI20050725000909, I20160503000287
Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignment

Medicare enrollment records show Mark Nitzberg reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Mark C. Nitzberg, P.C.
1.7 mi
Gastroenterology
380 R MERRIMACK ST., STE. 2C
Methuen, MA 01844
  • Reassigned Medicare billing, Massachusetts and New Hampshire enrollments
NPI 1992900013 (978) 681-1977

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

Areas of Expertise CMS Part B claims 10

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more 99213
This is a routine visit for patients who have already been seen by the healthcare provider. During this approximately 20-29 minute appointment, your health status will be evaluated and any necessary treatments or tests will be discussed. It's a chance to address any health concerns you may have.
53 services45 patients
Biopsy of large bowel using a flexible endoscope 45380
A biopsy of the large bowel using a flexible endoscope is a procedure where a thin, flexible tube with a camera is inserted through the rectum to examine the bowel. If abnormal tissue is found, a small sample is taken for further examination. This helps in diagnosing conditions like inflammation, polyps, or cancer.
41 services40 patients
New patient office or other outpatient visit with low level of medical decision making, if using time, 30 minutes or more 99203
This service involves an initial office or outpatient visit for a new patient. The healthcare professional will spend 30-44 minutes understanding your health history, current issues, and discussing possible treatment plans. It's a comprehensive evaluation to start your healthcare journey.
34 services34 patients
Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope 43239
This procedure involves using a thin, flexible tube with a light and camera, known as an endoscope, to examine the esophagus, stomach, and upper part of the small intestine. Small tissue samples are taken for further examination to help diagnose various conditions.
28 services27 patients
Removal of polyps or growths of large bowel using an endoscope with mechanical snare 45385
This procedure involves using a thin, flexible tube called an endoscope to examine the large bowel. If any abnormal growths or polyps are found, a tool called a mechanical snare is used to remove them. This is a common method to prevent potential health issues.
25 services25 patients
Biopsy of large bowel using a flexible endoscope 45380
A biopsy of the large bowel using a flexible endoscope is a procedure where a thin, flexible tube with a camera is inserted through the rectum to examine the bowel. If abnormal tissue is found, a small sample is taken for further examination. This helps in diagnosing conditions like inflammation, polyps, or cancer.
24 services24 patients

Hospital Affiliations CMS Care Compare 4

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

Lawrence General Hospital

Acute Care Hospitals · Lawrence, MA
2/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number220010
LocationOne General StreetLawrence, MA 01842 · Essex County
Emergency services Birthing friendly

Northeast Hospital Corporation

Acute Care Hospitals · Beverly, MA
3/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number220033
Location85 Herrick StreetBeverly, MA 01915 · Essex County
Emergency services Birthing friendly

Holy Family Hospital

Acute Care Hospitals · Methuen, MA
2/5 CMS rating
OwnershipProprietary
CMS Certification Number220080
Location70 East StreetMethuen, MA 01844 · Essex County
Emergency services Birthing friendly

Winchester Hospital

Acute Care Hospitals · Winchester, MA
4/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number220105
Location41 Highland AvenueWinchester, MA 01890 · Middlesex County
Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 01844 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$134.47 typical visit price
range $58.86 – $177.36
Typical copayment $33.61 (range $14.71 – $44.34)
Most-billed visit code 99204
Established Patient
$103.48 typical visit price
range $19.11 – $144.84
Typical copayment $25.87 (range $4.77 – $36.21)
Most-billed visit code 99214
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

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 Nitzberg's NPI number?

The NPI number for Mark Nitzberg is 1881652758. It was assigned to this individual provider in the NPPES registry on May 2, 2006.

Where is Mark Nitzberg located?

Mark Nitzberg practices at 38R Merrimack St. Suite 2C, Methuen, MA 01844. The listed phone number is (978) 681-1977.

What is Mark Nitzberg's specialty?

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

Is Mark Nitzberg enrolled in Medicare?

Yes. Mark Nitzberg is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

Which organization bills Medicare for Mark Nitzberg's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Mark Nitzberg reassigns Medicare benefits to Mark C. Nitzberg, P.C. (Methuen, MA). The 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 Mark Nitzberg's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Mark Nitzberg accept?

Health plans from Anthem Blue Cross and Blue Shield list Mark Nitzberg 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.

Is Mark Nitzberg affiliated with any hospitals?

According to CMS data, Mark Nitzberg is affiliated with Lawrence General Hospital, Northeast Hospital Corporation, Holy Family Hospital and Winchester Hospital.

When was this NPI record last updated?

The NPPES record for Mark Nitzberg was last updated on November 16, 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.