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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Dr. William Detlev Rittmeyer, DO

Interventional Pain Medicine Physician in Libertyville, IL · enumerated 2018.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1770088189

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Registry record

Entity type Individual (Type 1)
Name Dr. William Detlev Rittmeyer
Credential DO
Sex Male
Practice address Libertyville, IL, 60048
Phone (847) 279-0061
Fax (847) 279-0069
Enumeration date Mar 27, 2018
Last updated in NPPES May 22, 2025

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

207L00000X Anesthesiology Physician Allopathic & Osteopathic Physicians · License 036.158666 (IL) Secondary
207LP2900X Pain Medicine (Anesthesiology) Physician Allopathic & Osteopathic Physicians · License 036.158666 (IL) Secondary
208VP0014X Interventional Pain Medicine Physician Allopathic & Osteopathic Physicians · License 036.158666 (IL) Primary
DO · Doctor of Osteopathic Medicine: A fully licensed physician trained in osteopathic medical schools, with the same practice rights as an MD. About the DO credential

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

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Frequently asked questions

Where does William Rittmeyer practice?
The practice location on file with NPPES is in Libertyville, IL. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for William Rittmeyer?
The National Provider Identifier (NPI) for William Rittmeyer is 1770088189, a Type 1 (individual) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2025-05-22.