Douglas Reznick, MD
Douglas Reznick, MD is a Hematology & Oncology Physician in Aurora, CO, registered under NPI 1124002456.
Getting there
The practice address on file is 1700 S POTOMAC ST, Aurora, CO 80012. 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 |
|---|---|---|
| DR.0034032 | CO | Hematology & Oncology Physician primary |
This provider holds licence DR.0034032 issued in CO. 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 - Medical Oncology
- PAC ID
- 8123918547
Medicare enrolment is recorded as approved under the provider type Practitioner - Medical Oncology. 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 Hematology & Oncology covers
An internist doctor of osteopathy that specializes in the treatment of the combination of hematology and oncology disorders. A doctor of osteopathy that is board eligible/certified by the American Osteopathic Board of Internal Medicine WAS able to obtain a Certificate of Special Qualifications in the field of Hematology and Oncology. The Certificate is NO longer offered. NUCC Health Care Provider Taxonomy, code 207RH0003X
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 | 1124002456 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Nov 30, 2005 |
| Last updated | Feb 17, 2025 |
| Status | Active |
| Sole proprietor | No |
| Credential | MD |
| Practice address |
1700 S POTOMAC ST Aurora, CO 80012 (303) 418-7600 Fax (303) 750-3137 |
| Mailing address |
7951 E MAPLEWOOD AVE STE 350 Greenwood Village, CO 80111 |
| Other identifiers |
96022531
(CO) |
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 | 1 | 2 | 4 | 0 | 0 | 2 | 4 | 5 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 1 | 4 | 4 | 0 | 0 | 4 | 4 | 1 |
Sum = 44 · next multiple of 10 = 50 · check digit = 6 · actual last digit = 6
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.