Mazen Zaitoon, M.D.
NPI 1013280965 · Internal Medicine Physician · Valparaiso, IN
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Mazen Zaitoon, M.D. is a Internal Medicine Physician provider in Valparaiso, IN (NPI 1013280965).
Provider details
- NPI number
- 1013280965
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- 01075647A (IN)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Student, Health Care
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
14 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
2,892 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 50 Minutes99233 | 1,122 | $114 |
| Hospital Discharge Day Management, More Than 30 Minutes99239 | 631 | $110 |
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 35 Minutes99232 | 576 | $76 |
| Initial Hospital Care With Moderate Level of Medical Decision Making, If Using Time, at Least 75 Minutes99223 | 521 | $167 |
| Hospital Discharge Day Management, 30 Minutes Or Less99238 | 42 | $78 |
Typical Medicare-allowed amounts for these services range $76–$167 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, not a price quote and not what you would be billed. Medicare Part B covers roughly an eighth of all NPIs (65+ skew); services with fewer than 11 beneficiaries are suppressed by CMS. Source: CMS Medicare Physician & Other Practitioners, by Provider & Service.
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 20 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Cefdinir | 32 | 32 |
| Atorvastatin Calcium | 27 | 27 |
| Furosemide | 27 | 25 |
| Amlodipine Besylate | 22 | 22 |
| Doxycycline Hyclate | 20 | 19 |
| Hydrocodone/Acetaminophenbrand: Hydrocodone-Acetaminophen | 20 | 20 |
| Metoprolol Tartrate | 19 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$222 across 3 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
- 2012-02-22
- Last updated
- 2015-10-05
Frequently asked questions
- What is Mazen Zaitoon's NPI number?
- Mazen Zaitoon's National Provider Identifier (NPI) is 1013280965, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Mazen Zaitoon's specialty?
- Mazen Zaitoon is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Mazen Zaitoon located?
- Mazen Zaitoon's practice location on file with NPPES is 85 East United States 6 Frontage, Valparaiso, IN 46383.
- What is Mazen Zaitoon's phone number?
- The practice phone number listed in the NPPES registry for Mazen Zaitoon is (219) 983-8300.
- Does Mazen Zaitoon accept Medicare?
- Mazen Zaitoon is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Mazen Zaitoon's NPI active?
- Yes — Mazen Zaitoon's NPI (1013280965) is active in the NPPES registry as of the last update on 2015-10-05.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.