DR. GREGORY O'NEAL CLARK M.D. - NPI 1053363952 - Internal Medicine in Buffalo Grove, IL

Q: What is Gregory Clark's NPI number?

The NPI number for Gregory Clark is 1053363952. It was assigned to this individual provider in the NPPES registry on May 17, 2006.

Q: What is Gregory Clark's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Endocrinology, Diabetes & Metabolism, with taxonomy code 207RE0101X.

Q: Is Gregory Clark enrolled in Medicare?

No. Gregory Clark has opted out of Medicare through October 22, 2026. Care is provided under private contracts, and Medicare does not pay for services furnished by providers who have opted out. The provider remains eligible to order and refer services for Medicare patients.

Q: When was this NPI record last updated?

The NPPES record for Gregory Clark was last updated on July 26, 2023. NPI Profile syncs with the weekly NPPES data releases published by CMS.

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About Dr. Gregory O'neal Clark M.d. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

DR. GREGORY O'NEAL CLARK M.D. (NPI 1053363952) is an individual endocrinology, diabetes & metabolism provider in Buffalo Grove, Illinois, licensed in Illinois (336.093729) and active in the NPI registry since May 2006. He has opted out of Medicare through October 22, 2026 and remains eligible to order and refer.

NPPES Registry Identity

NPI1053363952

Entity TypeIndividualMale

Primary Taxonomy207RE0101X

Provider Legal NameDR. GREGORY O'NEAL CLARKCredential: M.D.

Location Address355 W DUNDEE RD STE 110Buffalo Grove, IL 60089-3500

Mailing Address920 Grandview LnLake Forest, IL 60045-3914 · (443) 823-0583

Phone(847) 541-4878

Fax(847) 520-0500

Sole ProprietorYes

Enumeration DateMay 17, 2006

Last NPPES UpdateJuly 26, 2023

NPPES CertifiedJuly 26, 2023

✔ NPI 1053363952 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · Endocrinology, Diabetes & MetabolismAllopathic & Osteopathic Physicians

Taxonomy Code207RE0101X

License✔ Licensed in IL · 336.093729

Definition

An internist who concentrates on disorders of the internal (endocrine) glands such as the thyroid and adrenal glands. This specialist also deals with disorders such as diabetes, metabolic and nutritional disorders, obesity, pituitary diseases and menstrual and sexual problems.

355 W DUNDEE RD STE 110, Buffalo Grove, IL 60089

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Group Practice 1

Group TaxonomyThis provdier is a business group of one or more individual practitioners, all of who practice with the same area of specialization.193400000X SINGLE SPECIALTY GROUP

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

ⓘ

Opted out of Medicare

Dr. Gregory O'neal Clark M.d. has filed a Medicare opt-out affidavit. Services are provided under private contract between the provider and the patient, and are not billed to or reimbursed by Medicare. The opt-out is on file from October 22, 2020 through October 22, 2026.

Opt-Out Effective DateOctober 22, 2020

Opt-Out In Effect ThroughOctober 22, 2026Opt-out affidavits renew automatically every two years unless cancelled

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesAn opted-out provider can still order and refer for Medicare patients in the categories marked above, even though their own services are not covered.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 60089 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient

$137.43 typical visit price

range $59.81 – $181.38

Typical copayment $34.35 (range $14.95 – $45.34)

Most-billed visit code 99204

Established Patient

$105.07 typical visit price

range $19.15 – $147.12

Typical copayment $26.26 (range $4.78 – $36.78)

Most-billed visit code 99214

Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Other Providers at the Same Location NPPES 6

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

TOUCH OF HEALTH PHYSICIANS MANAGEMENT

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