Jason Peng, MD
Jason Peng, MD is a Sleep Medicine (Internal Medicine) Physician in Chicago, IL, registered under NPI 1124481270. This provider registers 4 separate taxonomy codes, which usually means they practise across more than one recognised specialty.
Getting there
The practice address on file is 676 N SAINT CLAIR ST STE 7-701, Chicago, IL 60611. 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 |
|---|---|---|
| 036149345 | IL | Sleep Medicine (Internal Medicine)… primary |
| 036149345 | IL | Critical Care Medicine (Internal… |
| 036149345 | IL | Pulmonary Disease Physician |
| 036149345 | IL | Hospitalist Physician |
This provider holds licence 036149345 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 - Critical Care (intensivists)
- PAC ID
- 9133413503
Medicare enrolment is recorded as approved under the provider type Practitioner - Critical Care (intensivists). 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 Sleep Medicine covers
An Internist who practices Sleep Medicine is certified in the subspecialty of sleep medicine and specializes in the clinical assessment, physiologic testing, diagnosis, management and prevention of sleep and circadian rhythm disorders. Sleep specialists treat patients of any age and use multidisciplinary approaches. Disorders managed by sleep specialists include, but are not limited to, sleep related breathing disorders, insomnia, hypersomnias, circadian rhythm sleep disorders, parasomnias and sleep related movement disorders. NUCC Health Care Provider Taxonomy, code 207RS0012X
All registered taxonomy codes
This provider registers 4 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 207RS0012X | Sleep Medicine (Internal Medicine) Physician Sleep Medicine | 036149345 | IL | primary |
| 207RC0200X | Critical Care Medicine (Internal Medicine) Physician Critical Care Medicine | 036149345 | IL | |
| 207RP1001X | Pulmonary Disease Physician Pulmonary Disease | 036149345 | IL | |
| 208M00000X | Hospitalist Physician | 036149345 | IL |
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 | 1124481270 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Apr 5, 2016 |
| Last updated | Jun 4, 2025 |
| Status | Active |
| Sole proprietor | No |
| Credential | MD |
| Practice address |
676 N SAINT CLAIR ST STE 7-701 Chicago, IL 60611 (312) 695-7950 Fax (312) 926-4771 |
| Mailing address |
251 E HURON ST Chicago, IL 60611 |
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 | 4 | 8 | 1 | 2 | 7 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 1 | 4 | 4 | 8 | 8 | 2 | 2 | 5 |
Sum = 60 · next multiple of 10 = 60 · check digit = 0 · actual last digit = 0
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.