Dr. Daniel J. Grzegorek, DO
- Medicare services, 2024
- 5,431
- Medicare patients, 2024
- 641
- Part D claims, 2024
- 11,602
- Hospital affiliations
- 1
- Industry payments
- $282
- Practice address
- 2443 Warrenville Rd, Lisle, IL 60532
- Practice phone
- Call (630) 300-1200
- Professional email
- Get professional email
- Personal email
- Get personal email
- Mobile number
- Get mobile number
Primary practice
The Springs at Monarch Landing
Lisle, Illinois
Find Dr. Grzegorek's professional email, personal email and mobile number
Dmand AI checks each channel through healthcare-specific waterfall enrichment. See what is on file with a free account, with practice phones, licenses and affiliations.
Dr. Daniel J. Grzegorek is an internist in Lisle, Illinois
Dr. Grzegorek practices at The Springs at Monarch Landing in Lisle, Illinois.
Dr. Grzegorek's NPI, 1487651337, was assigned on July 7, 2005. Dr. Grzegorek graduated from Chicago College of Osteopathy in 1992. Dr. Grzegorek holds Illinois license 036-089211.
- NPI
- 1487651337NPI Registry (opens in a new tab)
- Medicare PAC ID
- 0749273183
- NPI enumeration date
- July 7, 2005
- NPI status
- Active
- Accepts Medicare assignment
- Yes
- Offers telehealth
- Yes
- Practice phone
- (630) 300-1200
- Professional email
- Get email
- Personal email
- Get email
- Mobile number
- Get number
- Sex
- Male
- Estimated age
- 60
- Medical school graduation
- 1992
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; Dmand AI Practice Data; and Doctors and Clinicians National Downloadable File (CMS)
Dr. Daniel J. Grzegorek practices at The Springs at Monarch Landing in Lisle, Illinois
Dr. Grzegorek's primary practice is The Springs at Monarch Landing, at 2443 Warrenville Rd, Lisle, IL 60532 in Dupage County. The practice phone is (630) 300-1200.
- The Springs at Monarch Landing2443 Warrenville Rd, Lisle, IL 60532 · Dupage CountyPhone(630) 300-1200
Sources: NPPES NPI Registry (CMS); and Dmand AI Practice Data
Dr. Daniel J. Grzegorek is affiliated with 10 sites of care and 1 medical group
Dr. Grzegorek's primary practice is The Springs at Monarch Landing in Lisle, Illinois. Dr. Grzegorek is also affiliated with UChicago Medicine AdventHealth Hinsdale. The medical group on file is DuPage Medical Group. Dmand AI also links Dr. Grzegorek to 3 more home health agencies, 3 hospices, 1 group practice or clinic and 1 skilled nursing facility, each named with a free account.
Sources: NPPES NPI Registry (CMS); Dmand AI Practice Data; Dmand AI Affiliation Data; and Dmand AI Org Hierarchy Data
Dmand AI tracks the EHR system at Dr. Daniel J. Grzegorek's practice
Dmand AI tracks the electronic health record (EHR) system at each site where Dr. Grzegorek practices, 9 sites in all. Vendor and product names are available with a free account.
| Site | EHR vendor and product |
|---|---|
| The Springs at Monarch Landing | Available with a free account |
| +9 more affiliated sites | Available with a free account |
Source: Dmand AI Technology Install Data
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Dr. Daniel J. Grzegorek is one of 5,652 internists in Illinois
Internal medicine is Dr. Grzegorek's primary specialty in the NPI Registry, under taxonomy code 207R00000X. Dr. Grzegorek is licensed in Illinois.
Specialties and state licenses
- Internal medicine, IllinoisPrimary
Internists near Dr. Grzegorek
Counts of internists with a Dmand AI profile, by place and practice. Each opens the list.
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; and Dmand AI Peer Benchmarks
Dr. Daniel J. Grzegorek billed Medicare for 5,431 services in 2024
CMS data shows 5,431 Medicare services from Dr. Grzegorek across 32 procedure codes in 2024, for 641 Medicare patients. Medicare paid $254,001 for them.
Dr. Grzegorek's Medicare services by type, 2023 to 2024
- 2023
- 2024
- Lab and pathology
- 2023: 1,7562024: 1,99313%
- Office and hospital visits
- 2023: 2,0612024: 1,9077%
- Other services
- 2023: 4672024: 86184%
- Surgery
- 2023: 5202024: 5618%
- Tests and treatments
- 2023: 1142024: 1094%
Where Dr. Grzegorek's Medicare services took place, 2024
- In an office4,46882%
- In a facility96318%
Dr. Grzegorek compared with the Illinois median for internists, 2024
- Dr. Grzegorek
- Illinois median
- Medicare services
- 5,431vs 5669.6 times
- Medicare patients
- 641vs 2083.1 times
- Part D claims
- 10,723vs 28437.8 times
Medians across 5,192 internists in Illinois with Dmand AI profiles that report each measure.
Dr. Grzegorek's most billed Medicare procedure codes, 2024
CMS publishes codes billed for 11 or more Medicare patients. Each label is the code family; CPT descriptions are licensed by the AMA.
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Medicare shows one payer. Book a meeting to get commercial claims data for Dr. Grzegorek and other internists in Illinois.
Sources: Medicare Physician & Other Practitioners - by Provider and Service (CMS), 2024 data; and Dmand AI Peer Benchmarks
Dr. Daniel J. Grzegorek treated 641 Medicare patients in 2024, average age 79
CMS counts 641 Medicare patients who saw Dr. Grzegorek in 2024. The largest group is 75 to 84, with 244 patients. 75% of them have high blood pressure, and 75% have high cholesterol. 9% are also on Medicaid. Their average risk score is 1.58, where 1.00 is the Medicare average, so they are sicker than most Medicare patients.
Across all payers, Dmand AI patient panel data puts Dr. Grzegorek's median patient age at 82, with 54% women.
Dr. Grzegorek's Medicare patients by age, 2024
CMS leaves out age groups with fewer than 11 patients.
Dr. Grzegorek's Medicare patients by sex, 2024
- Women36757%
- Men27443%
Chronic conditions among Dr. Grzegorek's Medicare patients, 2024
- High blood pressure75%
- High cholesterol75%
- Arthritis55%
- Chronic kidney disease38%
- Ischemic heart disease36%
- Diabetes31%
- Mood disorders29%
- Atrial fibrillation28%
Share of Medicare patients with each condition. A patient can have several.
Dr. Grzegorek's patients across all payers
Dmand AI patient panel data covers Medicare, Medicaid and commercial patients.
Patient panel by age, all payers
Median age 82
Patient panel by sex, all payers
- Women54%
- Men45%
Sources: Dmand AI Patient Panel Data; and Medicare Physician & Other Practitioners - by Provider (CMS), 2024 data
Dr. Daniel J. Grzegorek wrote 11,602 Medicare Part D claims in 2024
In 2024, Dr. Grzegorek wrote 11,602 Medicare Part D claims for 821 patients. 89% of them were for generic drugs. CMS names the drug for 10,723 of them, across 150 drugs with 11 or more claims each, at $479,311 in total drug cost. In 2023, CMS named 9,750 claims across 149 drugs.
Dr. Grzegorek's Part D claims by kind of drug, 2024
- Generic10,319 claims89%
- Brand-name1,242 claims11%
- Other41 claims0%
Dr. Grzegorek's most prescribed drugs by claims, 2024
CMS names a drug when it has 11 or more claims. Share is of the claims for drugs CMS names.
Drug classes CMS tracks in Dr. Grzegorek's Part D claims, 2024
- Opioids1%150 of 11,602 claims
- Antibiotics2%241 of 11,602 claims
- Antipsychotics, patients 65 and over1%85 of 11,602 claims
Share of all Part D claims for each drug class CMS reports on. Classes with no claims are left out.
Part D claims for drugs CMS names, 2023 to 2024
- 2023
- 2024
- Claims for drugs CMS names
- 2023: 9,7502024: 10,72310%
Drugs named by CMS: 150 in 2024, 149 in 2023.
Sources: Medicare Part D Prescribers - by Provider and Drug (CMS), 2024 data, released May 6, 2026; and Medicare Part D Prescribers - by Provider (CMS), 2024 data
Dr. Daniel J. Grzegorek offers telehealth to Medicare patients
Dr. Grzegorek accepts Medicare assignment, so Medicare's approved amount is taken as full payment. CMS lists Dr. Grzegorek as offering telehealth.
- Accepts Medicare assignment
- Yes
- Offers telehealth
- Yes
Source: Doctors and Clinicians National Downloadable File (CMS)
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Dr. Daniel J. Grzegorek received $282 in industry payments from 2019 to 2022
CMS Open Payments shows 7 general payments to Dr. Grzegorek from 4 drug and device companies from 2019 to 2022. Food and beverage make up the largest share, 100% of the total. Janssen Pharmaceuticals, Inc paid the most, $155.
General payments to Dr. Grzegorek by program year, 2019 to 2022
Companies that paid Dr. Grzegorek the most, 2019 to 2022
Share is of all general payments to this clinician.
Source: Open Payments (CMS), 2025 data, released July 7, 2026
Dr. Daniel J. Grzegorek graduated from Chicago College of Osteopathy
Dr. Grzegorek graduated from Chicago College of Osteopathy in 1992.
- Medical school
Source: Dmand AI Professional Profile Data
Sources for Dr. Daniel J. Grzegorek's profile data
| Data on this page | Source |
|---|---|
| NPI, name, sex, specialty and licenses | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Professional Profile Data |
| Practice locations and phone | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Practice Data |
| Primary practice, affiliations and health system | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Practice DataDmand AI Affiliation DataDmand AI Org Hierarchy Data |
| Medicare services and procedure codes | Medicare Physician & Other Practitioners - by Provider and Service (CMS) (opens in a new tab) |
| State medians for the same specialty | Dmand AI Peer Benchmarks |
| Medicare patients and the all-payer patient panel | Dmand AI Patient Panel DataMedicare Physician & Other Practitioners - by Provider (CMS) (opens in a new tab) |
| Part D prescribing | Medicare Part D Prescribers - by Provider and Drug (CMS) (opens in a new tab)Medicare Part D Prescribers - by Provider (CMS) (opens in a new tab) |
| MIPS scores, telehealth, assignment and procedure percentiles | Doctors and Clinicians National Downloadable File (CMS) (opens in a new tab) |
| Industry payments | Open Payments (CMS) (opens in a new tab) |
| Training, board certification and memberships | Dmand AI Professional Profile Data |
| EHR at each practice site | Dmand AI Technology Install Data |
| Similar physicians | Dmand AI Affiliation Data |
Data last refreshed October 2026Report an inaccuracyRemove my information
FAQ
Frequently asked questions about Dr. Daniel J. Grzegorek
Spotted something out of date? Email hello@dmand.ai and we will check the record. Contact details live in the free trial.
What is Dr. Daniel J. Grzegorek's NPI number?
Dr. Daniel J. Grzegorek's NPI number is 1487651337. It was assigned on July 7, 2005, and it is active in the NPI Registry.
What kind of doctor is Dr. Daniel J. Grzegorek?
Dr. Daniel J. Grzegorek is an internist in Lisle, Illinois. The primary specialty in the NPI Registry is Internal Medicine Physician (taxonomy code 207R00000X).
Where does Dr. Daniel J. Grzegorek practice?
Dr. Grzegorek practices at 2443 Warrenville Rd, Lisle, IL 60532. Dr. Grzegorek's primary practice is The Springs at Monarch Landing in Lisle, Illinois. Dmand AI also links Dr. Grzegorek to 3 home health agencies, 3 hospices, 1 group practice or clinic and 1 skilled nursing facility.
What is Dr. Daniel J. Grzegorek's office phone number?
The practice phone on file for Dr. Grzegorek is (630) 300-1200.
What is Dr. Daniel J. Grzegorek's medical license number?
Dr. Grzegorek holds Illinois license 036-089211.
Which hospitals is Dr. Daniel J. Grzegorek affiliated with?
Dr. Grzegorek is affiliated with UChicago Medicine AdventHealth Hinsdale.
What medical group is Dr. Daniel J. Grzegorek part of?
Dr. Grzegorek is linked to DuPage Medical Group.
Does Dr. Daniel J. Grzegorek accept Medicare?
Yes. CMS data shows Dr. Grzegorek billed Medicare for 5,431 services in 2024, and Dr. Grzegorek accepts Medicare assignment.
Does Dr. Daniel J. Grzegorek offer telehealth?
Yes. The CMS Doctors and Clinicians file lists Dr. Grzegorek as offering telehealth services.
How many Medicare patients does Dr. Daniel J. Grzegorek see?
CMS counts 641 Medicare patients who saw Dr. Grzegorek in 2024, with an average age of 79.
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What services does Dr. Daniel J. Grzegorek bill to Medicare?
In 2024, Dr. Grzegorek's most billed Medicare services were office visit, established patient (99214), surgery: heart and blood vessels (36415) and nursing facility care (99308).
Where did Dr. Daniel J. Grzegorek go to medical school?
Dr. Grzegorek graduated from Chicago College of Osteopathy in 1992.
What drugs does Dr. Daniel J. Grzegorek prescribe most?
In 2024 Medicare Part D data, Dr. Grzegorek's most prescribed drugs by claims were Atorvastatin Calcium, Levothyroxine Sodium and Amlodipine Besylate.
Has Dr. Daniel J. Grzegorek received payments from drug or device companies?
CMS Open Payments shows $282 in general payments to Dr. Grzegorek from 4 companies from 2019 to 2022. The largest total came from Janssen Pharmaceuticals, Inc.
How long has Dr. Daniel J. Grzegorek been practicing?
Dr. Grzegorek graduated from medical school in 1992, 34 years ago.
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