Mazen Najjar, M.D.
NPI 1245342393 · Infectious Disease Physician · Grand Blanc, MI
Enrolled with Medicare as Practitioner - Infectious Disease · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Mazen Najjar, M.D. is a Infectious Disease Physician provider in Grand Blanc, MI (NPI 1245342393).
Provider details
- NPI number
- 1245342393
- Entity type
- Individual
- Primary specialty
- Infectious Disease PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- Yes
- License
- 4301087544 (MI)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
19 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)25% of score
2,338 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
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 .
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) |
|---|---|---|
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 35 Minutes99232 | 1,733 | $75 |
| Initial Hospital Care With Straightforward Or Low-Level Medical Decision Making, If Using Time, at Least 55 Minutes99222 | 303 | $124 |
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 139 | $113 |
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 50 Minutes99233 | 74 | $112 |
| Subsequent Hospital Care With Straightforward Or Low Level of Medical Decision Making, Per Day, If Using Time, at Least 25 Minutes99231 | 45 | $47 |
| Initial Hospital Care With Moderate Level of Medical Decision Making, If Using Time, at Least 75 Minutes |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 27 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Vancomycin Hcl | 112 | 33 |
| Bictegrav/Emtricit/Tenofov Alabrand: Biktarvy | 97 | 11 |
| Amoxicillin/Potassium Clavbrand: Amoxicillin-Clavulanate Potass | 76 | 38 |
| Daptomycin | 68 | 18 |
| Ceftriaxone Sodiumbrand: Ceftriaxone | 61 | 15 |
| Cephalexin | 53 | 18 |
| Doxycycline Hyclate | 50 | 26 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$515 across 32 records (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-08-31
- Last updated
- 2007-10-05
Frequently asked questions
- What is Mazen Najjar's NPI number?
- Mazen Najjar's National Provider Identifier (NPI) is 1245342393, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Mazen Najjar's specialty?
- Mazen Najjar is listed in the NPPES registry with a primary specialty of Infectious Disease Physician (Allopathic & Osteopathic Physicians).
- Where is Mazen Najjar located?
- Mazen Najjar's practice location on file with NPPES is 4644 Genesys Pkwy, Grand Blanc, MI 48439-8067.
- What is Mazen Najjar's phone number?
- The practice phone number listed in the NPPES registry for Mazen Najjar is (810) 606-7125.
- Does Mazen Najjar accept Medicare?
- Mazen Najjar is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Mazen Najjar's NPI active?
- Yes — Mazen Najjar's NPI (1245342393) is active in the NPPES registry as of the last update on 2007-10-05.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.