John Costantino, D.O.
John Costantino, D.O. is a Nephrology Physician in Phoenix, AZ, registered under NPI 1235243361. 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 650 E INDIAN SCHOOL RD, Phoenix, AZ 85012. 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 |
|---|---|---|
| 2472 | AZ | Nephrology Physician primary |
This provider holds licence 2472 issued in AZ. 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
- Order And Referring Only - Nephrology
- PAC ID
- 5991959397
- Enrollment ID
- I20130213000146
Medicare enrolment is recorded as approved under the provider type Order And Referring Only - Nephrology. Being enrolled means the provider can bill Medicare; it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.
What Nephrology covers
An internist who treats disorders of the kidney, high blood pressure, fluid and mineral balance and dialysis of body wastes when the kidneys do not function. This specialist consults with surgeons about kidney transplantation. NUCC Health Care Provider Taxonomy, code 207RN0300X
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 | 1235243361 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Aug 18, 2006 |
| Last updated | Jul 8, 2007 |
| Status | Active |
| Sole proprietor | Yes |
| Credential | D.O. |
| Practice address |
650 E INDIAN SCHOOL RD Phoenix, AZ 85012 (602) 277-5551 Fax (602) 212-2096 |
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 | 2 | 3 | 5 | 2 | 4 | 3 | 3 | 6 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 2 | 6 | 5 | 4 | 4 | 6 | 3 | 3 |
Sum = 59 · next multiple of 10 = 60 · check digit = 1 · actual last digit = 1
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.