Louisa Ziglar, MD
Louisa Ziglar, MD is a Rheumatology Physician in Frederick, MD, registered under NPI 1538336151.
Getting there
The practice address on file is 161 THOMAS JOHNSON DR STE 250, Frederick, MD 21702. 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 |
|---|---|---|
| D80134 | MD | Rheumatology Physician primary |
This provider holds licence D80134 issued in MD. 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 - Rheumatology
- PAC ID
- 2264556802
Enrolled in Medicare 2 times, across 2 states:
| State | Enrollment ID | Provider type |
|---|---|---|
| District of Columbia | I20150810002410 | Practitioner - Rheumatology |
| Maryland | I20181017000712 | Practitioner - Rheumatology |
Medicare enrolment is recorded as approved under the provider type Practitioner - Rheumatology. There are 2 separate enrolment records across 2 states (DC, MD). Multiple enrolments usually mean the provider bills Medicare from more than one practice location, or has kept an earlier enrolment after moving. Each record carries its own enrolment ID, listed above. 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 Rheumatology covers
An internist who treats diseases of joints, muscle, bones and tendons. This specialist diagnoses and treats arthritis, back pain, muscle strains, common athletic injuries and "collagen" diseases. NUCC Health Care Provider Taxonomy, code 207RR0500X
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 | 1538336151 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | May 13, 2008 |
| Last updated | Feb 5, 2026 |
| Status | Active |
| Sole proprietor | No |
| Credential | MD |
| Practice address |
161 THOMAS JOHNSON DR STE 250 Frederick, MD 21702 (301) 942-7600 Fax (301) 694-0187 |
| Mailing address |
7361 CALHOUN PL STE 600 Rockville, MD 20855 |
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 | 5 | 3 | 8 | 3 | 3 | 6 | 1 | 5 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 5 | 6 | 8 | 6 | 3 | 3 | 1 | 1 |
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.