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Oak Brook Allergists Sc

Oak Brook Allergists Sc is a healthcare organization registered as Allergy & Immunology Physician in Elmhurst, IL, holding Type 2 (organization) NPI 1700819117 since 2006. The authorized official on file is David Knysak, President.

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NPI 1700819117
Entity type Organization (Type 2)
Legal business name Oak Brook Allergists Sc
Practice address 360 W BUTTERFIELD RD STE 140, Elmhurst, IL, 60126
Phone 6305740460
Fax 6305740470
Enumeration date 2006-07-09
Last updated in NPPES 2018-03-12

Authorized official

Name David Knysak
Title President
Phone 6305740460

Taxonomy & classification

Taxonomy code Specialty Primary License State
207K00000X Allergy & Immunology Physician Primary 042000355 IL
Copy-ready billing details
Provider: Oak Brook Allergists Sc
NPI: 1700819117
Taxonomy: 207K00000X (Allergy & Immunology Physician)
Address: 360 W BUTTERFIELD RD STE 140, Elmhurst, IL, 60126

Providers at this address

NPI Name Type Specialty Location
1609876101 David Knysak Individual Allergy & Immunology Physician Elmhurst, IL
1720331473 Tammy Laas Individual Family Nurse Practitioner Elmhurst, IL
1750775185 Zachary Rubin Individual Allergy & Immunology Physician Elmhurst, IL

Verify this record

Cross-check NPI 1700819117 against the authoritative CMS record: view Oak Brook Allergists Sc 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

Who is the authorized official for Oak Brook Allergists Sc?
NPPES lists David Knysak (President) as the authorized official for this organization.
What is the NPI number for Oak Brook Allergists Sc?
The NPI for Oak Brook Allergists Sc is 1700819117, a Type 2 (organization) record in the CMS NPPES registry.

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2018-03-12.