Oscar Alonso, M.D.
Oscar Alonso, M.D. is a Specialist in Downers Grove, IL, registered under NPI 1447285739. 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 1121 WARREN AVE STE 200, Downers Grove, IL 60515. 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 |
|---|---|---|
| 036064967 | IL | Specialist primary |
This provider holds licence 036064967 issued in IL. 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 - Otolaryngology
- PAC ID
- 0042103442
Medicare enrolment is recorded as approved under the provider type Practitioner - Otolaryngology. 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 Specialist covers
An individual educated and trained in an applied knowledge discipline used in the performance of work at a level requiring knowledge and skills beyond or apart from that provided by a general education or liberal arts degree. NUCC Health Care Provider Taxonomy, code 174400000X
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 | 1447285739 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Jul 12, 2006 |
| Last updated | Apr 16, 2021 |
| Status | Active |
| Sole proprietor | Yes |
| Credential | M.D. |
| Practice address |
1121 WARREN AVE STE 200 Downers Grove, IL 60515 (630) 960-5310 Fax (630) 969-7841 |
| Mailing address |
1121 WARREN AVE STE 200 Downers Grove, IL 60515 |
| Other identifiers |
31602726
· BLUE CROSS BLUE SHIELD (IL) 036064967 (IL) 036064967 · IL STATE LICENSE NUMBER (IL) |
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 | 4 | 4 | 7 | 2 | 8 | 5 | 7 | 3 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 4 | 8 | 7 | 4 | 8 | 1 | 7 | 6 |
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.