Andrew Duke, M.D.
Andrew Duke, M.D. is a Critical Care Medicine (Internal Medicine) Physician in Fullerton, CA, registered under NPI 1013986959.
Getting there
The practice address on file is 100 E VALENCIA MESA DR, Fullerton, CA 92835. 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 |
|---|---|---|
| A74218 | CA | Critical Care Medicine (Internal… primary |
This provider holds licence A74218 issued in CA. 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 - Pulmonary Disease
- PAC ID
- 8527097187
Medicare enrolment is recorded as approved under the provider type Practitioner - Pulmonary Disease. 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 Critical Care Medicine covers
An internist who diagnoses, treats and supports patients with multiple organ dysfunction. This specialist may have administrative responsibilities for intensive care units and may also facilitate and coordinate patient care among the primary physician, the critical care staff and other specialists. NUCC Health Care Provider Taxonomy, code 207RC0200X
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 | 1013986959 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Mar 14, 2006 |
| Last updated | May 19, 2025 |
| Status | Active |
| Sole proprietor | No |
| Credential | M.D. |
| Practice address |
100 E VALENCIA MESA DR Fullerton, CA 92835 (714) 992-3969 |
| Mailing address |
PO BOX 1753 Anaheim, CA 92815 |
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 | 1 | 3 | 9 | 8 | 6 | 9 | 5 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 0 | 2 | 3 | 9 | 8 | 3 | 9 | 1 |
Sum = 61 · next multiple of 10 = 70 · 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.