Mark Nitzberg, M.D.
NPI 1881652758 · Gastroenterology Physician · Methuen, MA
Enrolled with Medicare as Practitioner - Gastroenterology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Mark Nitzberg, M.D. is a Gastroenterology Physician provider in Methuen, MA (NPI 1881652758).
Provider details
- NPI number
- 1881652758
- Entity type
- Individual
- Primary specialty
- Gastroenterology PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- Yes
- License
- 74584 (MA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
20 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)28% of score
270 Medicare services, 2024 (ranked within specialty)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 53 | $88 |
| Biopsy of Large Bowel Using a Flexible Endoscope45380 | 41 | $193 |
| New Patient Office Or Other Outpatient Visit With Low Level of Medical Decision Making, If Using Time, 30 Minutes Or More99203 | 34 | $104 |
| Biopsy of Esophagus, Stomach, And/Or Upper Small Bowel Using a Flexible Endoscope43239 | 28 | $107 |
| Removal of Polyps Or Growths of Large Bowel Using an Endoscope With Mechanical Snare45385 | 25 | $248 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 22 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Omeprazole | 222 | 77 |
| Atorvastatin Calcium | 66 | 18 |
| Pantoprazole Sodium | 54 | 20 |
| Losartan Potassium | 35 | — |
| Peg3350/Sod Sulf,bicarb,cl/Kclbrand: Gavilyte-G | 33 | 30 |
| Triamterene/Hydrochlorothiazidbrand: Triamterene-Hydrochlorothiazid | 29 | — |
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-05-02
- Last updated
- 2017-11-16
Frequently asked questions
- What is Mark Nitzberg's NPI number?
- Mark Nitzberg's National Provider Identifier (NPI) is 1881652758, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Mark Nitzberg's specialty?
- Mark Nitzberg is listed in the NPPES registry with a primary specialty of Gastroenterology Physician (Allopathic & Osteopathic Physicians).
- Where is Mark Nitzberg located?
- Mark Nitzberg's practice location on file with NPPES is 38r Merrimack St., Methuen, MA 01844.
- What is Mark Nitzberg's phone number?
- The practice phone number listed in the NPPES registry for Mark Nitzberg is (978) 681-1977.
- Does Mark Nitzberg accept Medicare?
- Mark Nitzberg is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Mark Nitzberg's NPI active?
- Yes — Mark Nitzberg's NPI (1881652758) is active in the NPPES registry as of the last update on 2017-11-16.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.