GREGORY O'NEAL CLARK, M.D.

Internal Medicine, Endocrinology, Diabetes & Metabolism

✓ Prescribes GLP-1Accepts Medicare

Confirmed GLP-1 prescriber

Public Medicare Part D data (2024) shows this provider prescribed GLP-1 medication — including Ozempic to Medicare patients. This reflects past prescribing history, not a guarantee they will prescribe for you — always confirm directly with the provider.

Location & contact

355 W DUNDEE RD STE 110

Buffalo Grove, IL 60089

847-541-4878

NPI: 1053363952

Before you book

Confirm this provider accepts your Part D or Medicare Advantage plan, and ask whether they have filed a Medicare GLP-1 prior authorization before. Not sure you qualify yet? Take the 2-minute eligibility quiz or read the Medicare & GLP-1 coverage guide. You can also browse other Buffalo Grove providers or all Illinois providers.

Where this directory comes from

Listings are sourced from the National Plan & Provider Enumeration System (NPPES), the public provider registry maintained by the U.S. Centers for Medicare & Medicaid Services, and include licensed providers in relevant specialties. A listing is a starting point, not a recommendation: it does not confirm that a provider currently prescribes GLP-1 medications, accepts your plan, or is taking new patients. Always confirm details directly with the provider before scheduling care.

About the “Prescribes GLP-1” tag

The green “✓ Prescribes GLP-1” tag means public CMS Medicare Part D data shows this provider prescribed a GLP-1 medication to Medicare patients in a recent year. It reflects past prescribing history, not a guarantee they will prescribe for you today.

If a provider does not have this tag, it does not mean they won't prescribe a GLP-1. Many doctors and clinics prescribe GLP-1 medications but do not appear in the CMS data — for example, providers who began prescribing recently, those who primarily prescribe through commercial insurance rather than Medicare Part D, or those whose claims fall below the CMS reporting threshold. Your own doctor may be willing and able to prescribe a GLP-1 even if they are not listed here or do not have this tag.

Your doctor isn't listed?

This directory does not include every doctor who can prescribe GLP-1 medications — it is one starting point among many. Ask your own primary care doctor or endocrinologist first. Any licensed prescriber can write a GLP-1 prescription and submit the Medicare prior authorization. The registry may also classify your doctor under a different specialty than we filter for. If you know a provider who should be listed, use the suggestion form on any state or city page to let us know.

About this listing

GLP1 Almanac is an independent reference site. This listing is provided for informational purposes only and does not constitute a referral, endorsement, or medical advice. We are not affiliated with this provider. Always confirm credentials, Medicare participation, and current availability directly before scheduling care.