John Herzog, MD
John Herzog, MD is a Cardiovascular Disease Physician in Greenville, MS, registered under NPI 1093734949. NPPES records them as a sole proprietor, meaning the practice is not incorporated as a separate legal entity.
Getting there
The practice address on file is 1421 E UNION ST, Greenville, MS 38703. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| 09800 | MS | Cardiovascular Disease Physician primary |
This provider holds licence 09800 issued in MS. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
- Status
- Approved
- Provider type
- Practitioner - Cardiovascular Disease (cardiology)
- PAC ID
- 1355390964
Medicare enrolment is recorded as approved under the provider type Practitioner - Cardiovascular Disease (cardiology). This means the provider is enrolled to bill Medicare, though it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.
What Cardiovascular Disease covers
An internist who specializes in diseases of the heart and blood vessels and manages complex cardiac conditions such as heart attacks and life-threatening, abnormal heartbeat rhythms. NUCC Health Care Provider Taxonomy, code 207RC0000X
The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.
Full NPPES record
An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.
| NPI | 1093734949 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Jul 19, 2006 |
| Last updated | Aug 21, 2020 |
| Status | Active |
| Sole proprietor | Yes |
| Credential | MD |
| Practice address |
1421 E UNION ST Greenville, MS 38703 (662) 335-0183 Fax (662) 335-7184 |
| Mailing address |
PO BOX 5368 Greenville, MS 38704 |
| Other identifiers |
060000624
· MEDICARE (MS) 00123017 (MS) 126236001 (AR) |
Number check
How the check works, step by step
Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.
| Digit | 8 | 0 | 8 | 4 | 0 | 1 | 0 | 9 | 3 | 7 | 3 | 4 | 9 | 4 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 0 | 9 | 3 | 5 | 3 | 8 | 9 | 8 |
Sum = 71 · next multiple of 10 = 80 · check digit = 9 · actual last digit = 9
A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.