JOHN ONYEMAECHI NNADI MD
NPI 1558506782
Internal Medicine - Infectious Disease in Baton Rouge, LA
About John Onyemaechi Nnadi Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
JOHN ONYEMAECHI NNADI MD (NPI 1558506782) is an individual infectious disease provider in Baton Rouge, Louisiana, licensed in Louisiana (MD.202997) and active in the NPI registry since December 2008. He is enrolled in Medicare PECOS, is affiliated with Baton Rouge General Medical Center, and maintains 2 additional practice locations.
NPPES Registry Identity
Specialties & Licenses 2
Secondary Practice Locations 2
Other Identifiers 2
Accepted 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
John Onyemaechi Nnadi Md 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.
Medicare Billing Reassignments
11Medicare enrollment records show John Nnadi reassigns Medicare billing to 11 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Baton Rouge, LA 70816
- Reassigned Medicare billing, Louisiana enrollment
- 156 clinicians in this Medicare group
Baton Rouge, LA 70816
- Reassigned Medicare billing, Louisiana enrollment
- 4,559 clinicians in this Medicare group
Baton Rouge, LA 70810
- Reassigned Medicare billing, Louisiana enrollment
- 21 clinicians in this Medicare group
Jonesboro, LA 71251
- Reassigned Medicare billing, Louisiana enrollment
- 16 clinicians in this Medicare group
Humble, TX 77338
- Reassigned Medicare billing, Louisiana enrollment
- 169 clinicians in this Medicare group
Clarksdale, MS 38614
- Reassigned Medicare billing, Mississippi enrollment
- 170 clinicians in this Medicare group
Austin, TX 78705
- Reassigned Medicare billing, Texas enrollment
- 140 clinicians in this Medicare group
Denver, CO 80246
- Reassigned Medicare billing, Louisiana enrollment
Milford, DE 19963
- Reassigned Medicare billing, Delaware enrollment
- Also billed through NPI 1467546135 (Delaware)
- 299 clinicians in this Medicare group
Kingsford, MI 49802
- Reassigned Medicare billing, Michigan enrollment
- 440 clinicians in this Medicare group
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 9
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.
Hospital Affiliations CMS Care Compare 4
Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.
Baton Rouge General Medical Center
Acute Care Hospitals · Baton Rouge, LAOchsner Medical Center - Baton Rouge
Acute Care Hospitals · Baton Rouge, LATrios Health
Acute Care Hospitals · Kennewick, WALourdes Medical Center
Critical Access Hospitals · Pasco, WAPhysician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 70816 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.
Other Providers at the Same Location NPPES 20
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
BATON ROUGE, LA 70816
BATON ROUGE, LA 70816
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 John Nnadi's NPI number?
The NPI number for John Nnadi is 1558506782. It was assigned to this individual provider in the NPPES registry on December 2, 2008.
Where is John Nnadi located?
John Nnadi practices at 17000 Medical Center Dr, Baton Rouge, LA 70816. The listed phone number is (225) 752-2470.
What is John Nnadi's specialty?
The primary specialty registered for this NPI is Internal Medicine, specializing in Infectious Disease, with taxonomy code 207RI0200X.
Is John Nnadi enrolled in Medicare?
Yes. John Nnadi 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 organizations bill Medicare for John Nnadi's services?
According to the CMS Revalidation Reassignment List (October 2026 release), John Nnadi reassigns Medicare benefits to 11 organizations: Mayfair Physician Services, LLC (Baton Rouge, LA), Ochsner Clinic LLC (Baton Rouge, LA), Homedica Of Louisiana, LLC (Baton Rouge, LA), Mercy Medical Health Center (Jonesboro, LA), Hospitalist Medicine Physicians Of Texas, PLLC (Humble, TX) and 6 more organizations, listed in the Medicare section above. Each 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 John Nnadi's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does John Nnadi accept?
Health plans from Ambetter Health, Ambetter from Arkansas Health & Wellness, Ambetter from Louisiana Healthcare Connections, Ambetter from Superior HealthPlan and Ambetter of Alabama and 5 other insurers list John Nnadi 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 John Nnadi affiliated with any hospitals?
According to CMS data, John Nnadi is affiliated with Baton Rouge General Medical Center, Ochsner Medical Center - Baton Rouge, Trios Health and Lourdes Medical Center.
When was this NPI record last updated?
The NPPES record for John Nnadi was last updated on November 17, 2022. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 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.
# John Onyemaechi Nnadi, MD · NPI 1558506782
Infectious Disease physician in Baton Rouge, Louisiana. Individual provider, active in the CMS NPPES registry since December 2, 2008.
## Identity
- **NPI:** 1558506782 (Entity type: Individual)
- **Enumerated:** December 2, 2008
- **Primary specialty:** Internal Medicine - Infectious Disease · taxonomy 207RI0200X
- **State license:** MD.202997 (Louisiana)
- **Sole proprietor:** No
## Practice location
- **Address:** 17000 MEDICAL CENTER DR, Baton Rouge, LA 70816-3246
- **Phone:** (225) 752-2470
## Medicare
- **Medicare:** Enrolled (PECOS); accepts Medicare assignment
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment, home health, power mobility devices
- **Bills Medicare through:** 11 organizations under Medicare reassignment (form CMS-855R): Mayfair Physician Services, LLC (NPI 1831688365, Baton Rouge, LA); Ochsner Clinic LLC (NPI 1962972109, Baton Rouge, LA); Homedica Of Louisiana, LLC (NPI 1174866479, Baton Rouge, LA); Mercy Medical Health Center (NPI 1063945434, Jonesboro, LA); Hospitalist Medicine Physicians Of Texas, PLLC (NPI 1629307095, Humble, TX); and 6 more · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Other, class of 1999
## Record status
- **NPPES last updated:** November 17, 2022
- **Other identifiers:** Medicaid 1883115 (LA); Other 05202301 (MS)
---
Source: [NPI Profile](https://npiprofile.com/npi/1558506782) · Data from the CMS NPPES public registry.