William Rittmeyer, DO
William Rittmeyer, DO is an Interventional Pain Medicine Physician in Libertyville, IL, registered under NPI 1770088189. This provider registers 3 separate taxonomy codes, which usually means they practise across more than one recognised specialty. 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 890 GARFIELD AVE STE 103, Libertyville, IL 60048. 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 |
|---|---|---|
| 036.158666 | IL | Anesthesiology Physician |
| 036.158666 | IL | Pain Medicine (Anesthesiology) Physician |
| 036.158666 | IL | Interventional Pain Medicine Physician primary |
This provider holds licence 036.158666 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 - Anesthesiology
- PAC ID
- 5799110557
- Enrollment ID
- I20230303001952
Medicare enrolment is recorded as approved under the provider type Practitioner - Anesthesiology. 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 Interventional Pain Medicine covers
Interventional Pain Medicine is the discipline of medicine devoted to the diagnosis and treatment of pain and related disorders principally with the application of interventional techniques in managing subacute, chronic, persistent, and intractable pain, independently or in conjunction with other modalities of treatment. NUCC Health Care Provider Taxonomy, code 208VP0014X
All registered taxonomy codes
This provider registers 3 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 207L00000X | Anesthesiology Physician | 036.158666 | IL | |
| 207LP2900X | Pain Medicine (Anesthesiology) Physician Pain Medicine | 036.158666 | IL | |
| 208VP0014X | Interventional Pain Medicine Physician Interventional Pain Medicine | 036.158666 | IL | primary |
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 | 1770088189 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Mar 27, 2018 |
| Last updated | May 22, 2025 |
| Status | Active |
| Sole proprietor | Yes |
| Gender | Male |
| Credential | DO |
| Practice address |
890 GARFIELD AVE STE 103 Libertyville, IL 60048 (847) 279-0061 Fax (847) 279-0069 |
| Mailing address |
29373 NETWORK PL Chicago, IL 60673 |
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 | 7 | 7 | 0 | 0 | 8 | 8 | 1 | 8 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 7 | 5 | 0 | 0 | 8 | 7 | 1 | 7 |
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.