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Willowbrook Clinic

Family Medicine Physician in Downers Grove, IL · enumerated 2006 · authorized official Ataullah Arain, Physician.

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

National Provider Identifier

1740368927

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Registry record

Entity type Organization (Type 2)
Legal business name Willowbrook Clinic
Practice address 4121 Fairview Ave Ste L2, Downers Grove, IL, 60515
Phone (630) 674-1160
Fax (866) 261-3402
Enumeration date Nov 2, 2006
Last updated in NPPES Dec 29, 2008

Taxonomy & classification

207Q00000X Family Medicine Physician Allopathic & Osteopathic Physicians · License 036054825 (IL) Primary

Authorized official

Name Ataullah Arain
Title Physician
Phone (630) 674-1160

Other identifiers

Identifier Type State Issuer
036054825 Medicaid IL -
02201168 Other IL BCBS OF IL

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

Who is the authorized official for Willowbrook Clinic?
NPPES lists Ataullah Arain (Physician) as the authorized official for this organization.
What is the NPI number for Willowbrook Clinic?
The NPI for Willowbrook Clinic is 1740368927, a Type 2 (organization) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2008-12-29.