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Douglas J Markham, DC

Douglas J Markham is a Chiropractor provider (Chiropractor) practicing in Thousand Oaks, CA, registered in the NPPES registry with NPI 1861573883 since 2006. The credential DC stands for Doctor of Chiropractic.

✓ Active NPI ✓ Valid NPI checksum Sole proprietor

NPI 1861573883
Entity type Individual (Type 1)
Name Douglas J Markham
Credential DC
Sex Male
Practice address Thousand Oaks, CA, 91360
Phone 8054966255
Fax 8054967288
Enumeration date 2006-10-17
Last updated in NPPES 2008-05-07

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

Taxonomy & licenses

Taxonomy code Specialty Primary License State
111N00000X Chiropractor Primary DC19530 CA

DC — Doctor of Chiropractic: A licensed chiropractor focusing on musculoskeletal and nervous system disorders. About the DC credential

Copy-ready billing details
Provider: Douglas Markham, DC
NPI: 1861573883
Taxonomy: 111N00000X (Chiropractor)
Address: Thousand Oaks, CA, 91360

Verify this record

Cross-check NPI 1861573883 against the authoritative CMS record: view Douglas J Markham on the official NPPES registry .

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. Read the full guide or validate an NPI number.

Frequently asked questions

Is NPI 1861573883 active?
Yes — as of the latest NPPES snapshot, NPI 1861573883 is active (record last updated 2008-05-07).
How do I verify Douglas Markham's NPI record?
Cross-check NPI 1861573883 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2008-05-07.