Lillie Cook
Physician Assistant β’ Chicago, IL
331 W Surf St Ste 912
Chicago, IL 606577227
This profile restates public CMS/NPPES data; T-MedInfo gives no medical advice — consult a licensed professional, and call 911 for emergencies.
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NPI assigned on March 2, 2022; this date does not establish years in practice.
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Published CMS data list 106 Medicare Part D prescriptions, including refills, in 2024.
Source: CMS, Medicare Part D Prescribers β by Provider and Drug, 2024. Published rows only; this is not a quality measure.
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Published Part D records, 2024:
- Metoclopramide Hcl β 48 prescription fills, including refills.
- Omeprazole β 26 prescription fills, including refills.
- Pantoprazole Sodium β 21 prescription fills, including refills.
Source: CMS, Medicare Part D Prescribers β by Provider and Drug, 2024. Drug names come from pharmacy claims. Listing a drug here is not an endorsement or a recommendation.
See all 4 records in the table Β· Guide: How to read Medicare Part D prescriber data
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Close to the middle for Part D prescriptions among clinicians listed under Physician Assistant in Chicago, IL (2024, 651 clinicians with data). Median for this group: 116. Middle half: 41 to 337.
Fewer Part D prescriptions than 65% of clinicians listed under Physician Assistant in Illinois (2024, 2,668 clinicians with data). Median for this group: 203. Middle half: 67 to 595.
Source: CMS, Medicare Part D Prescribers β by Provider and Drug, 2024. Billing and prescribing volume is not a quality rating.
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Medicare Part D prescriptions went from 26 in 2023 to 106 in 2024.
Source: CMS, Medicare Part D Prescribers β by Provider and Drug, 2023β2024.
Practice Location & Contact Primary Location
331 W Surf St Ste 912
Chicago, IL 606577227
Matched by practice address or phone in NPPES. A shared address or phone does not confirm that this clinician works there.
NPPES lists 1 additional practice-address record in Evanston, IL. See the list
Source: CMS NPPES NPI Registry, practice location records; release date unavailable.
CMS Doctors and Clinicians lists 1 group name: Illinois Gastroenterology Group Llc. See the list
Source: CMS Doctors and Clinicians National Downloadable File, release date unavailable.
Listings do not confirm current availability, employment or a shared ownership network.
Medicare Profile & Education
Source: CMS Doctors and Clinicians National Downloadable File
2021
What Public CMS Data Show
Physician Assistant: NPPES taxonomy is a reported classification, not proof of board certification.
30-day fills
198 standardized 30-day fills in 2024
CMS converts prescriptions to 30-day supplies so they can be compared. A 90-day prescription counts as about three 30-day fills.
What this does not show: 30-day fills
It is not a count of patients and not a measure of quality.
Part D drug cost
$1,099 in 2024
The total cost of these prescriptions in 2024, paid by Medicare drug plans, patients and other payers together.
It shows the total spending on drugs this clinician prescribed, not what any one patient paid.
What this does not show: Part D drug cost
A higher cost often reflects the type of medicines a specialty uses. It is not your out-of-pocket cost and not a measure of quality.
Source: CMS, Medicare Part D Prescribers β by Provider and Drug, 2024.
Open Payments general payments, program year 2025
All general payments: $570.23 across 27 records.
By nature of payment
- Food and Beverage: $491.23 across 26 records.
- Education: $79.00 across 1 record.
Reporting-company totals (3 largest of 10)
- Janssen Pharmaceuticals, Inc: $144.91 across 7 records.
- Gilead Sciences, Inc.: $141.05 across 5 records.
- ABBVIE INC.: $76.53 across 4 records.
A reported payment does not necessarily mean the financial relationship is improper and is not a measure of care quality. Clinicians can review and dispute these records.
Source: Calculated by T-MedInfo from CMS Open Payments general-payment records for program year 2025 (published June 30, 2026).
Years since graduation
5 years (graduated 2021)
CMS Doctors and Clinicians data list 2021 as the year this clinician finished professional school.
It tells you roughly how long ago the clinician finished school.
What this does not show: Years since graduation
It is not the number of years in practice, and more years does not mean better care.
Source: CMS Doctors and Clinicians National Downloadable File.
NPI first issued
2022
The year this clinician's National Provider Identifier (NPI) was issued. An NPI is a unique 10-digit ID that US health care providers use for billing.
What this does not show: NPI first issued
NPIs have been issued only since 2005, so this year is not necessarily when the clinician started practicing.
Source: CMS NPPES NPI Registry.
Accepts Medicare assignment
CMS data list this clinician as accepting Medicare assignment. This means agreeing to take the Medicare-approved amount as full payment for covered services.
With Original Medicare, you usually pay only your deductible and coinsurance, and the office sends the claim to Medicare for you.
Medicare assignment applies to Original Medicare. It does not tell you whether the clinician is in a Medicare Advantage plan's network, accepts other insurance, or is taking new patients.
Source: CMS Doctors and Clinicians; Medicare.gov, βDoes your provider accept Medicare as full payment?β
Telehealth (some services)
Recent Medicare claims show this clinician provided some services by telehealth, such as a video or phone visit.
You may be able to have some visits without going to the office. Ask which visits can be done by telehealth.
What this does not show: Telehealth (some services)
It does not mean all services are offered by telehealth, or that telehealth is covered by your plan.
Source: CMS, Telehealth Indicator on Medicare Care Compare (fact sheet, January 2023); CMS Doctors and Clinicians.
Enrolled in Medicare (PECOS)
Lillie Cook has a Medicare enrollment record in PECOS, the CMS system clinicians use to enroll so they can bill Medicare or order services for people with Medicare.
It does not show whether the clinician accepts assignment, is in your plan's network, or is taking new patients.
Source: CMS Medicare Fee-For-Service Public Provider Enrollment (PECOS); CMS Order and Referring file.
Can order Medicare-covered services
CMS lists Lillie Cook as eligible to order or refer Medicare Part B clinical laboratory and imaging services, durable medical equipment (DME) and home health services for people with Medicare.
Medicare pays for these items and services only when they are ordered by an eligible clinician.
What this does not show: Can order Medicare-covered services
It does not mean the clinician offers these services directly.
Source: CMS Medicare Fee-For-Service Public Provider Enrollment (PECOS); CMS Order and Referring file.
Compared with the same specialty in Chicago and Illinois
Billing and prescribing volume is not a quality rating.
Medicare Part D prescriptions
Close to the middle for clinicians listed under Physician Assistant in Chicago, IL (2024, 651 clinicians with data). Median for this group: 116. Middle half: 41 to 337.
Fewer Part D prescriptions than 65% of clinicians listed under Physician Assistant in Illinois (2024, 2,668 clinicians with data). Median for this group: 203. Middle half: 67 to 595.
Part D drug cost
Close to the middle for clinicians listed under Physician Assistant in Chicago, IL (2024, 651 clinicians with data). Median for this group: $1,977. Middle half: $320 to $34,048.
A lower Part D drug cost than 60% of clinicians listed under Physician Assistant in Illinois (2024, 2,668 clinicians with data). Median for this group: $3,018. Middle half: $535 to $48,132.
1,446 active clinicians are listed under Physician Assistant with a practice address in Chicago, IL (4,929 in Illinois).
Addresses are self-reported to NPPES and may be out of date.
Telehealth indicator in Chicago
17.4% of these 1,446 clinicians have the CMS telehealth indicator.
63.6% of these 1,446 clinicians are listed by CMS as accepting Medicare assignment.
CMS data by year
Changes may reflect reporting, coverage or privacy limits, not changes in care quality.
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Medicare Part D prescriptions
Medicare Part D prescriptions increased 308% from 26 in 2023 to 106 in 2024.
- 2023: 26
- 2024: 106
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30-day fills
30-day fills increased 560% from 30 in 2023 to 198 in 2024.
- 2023: 30
- 2024: 198
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Part D drug cost
Part D drug cost went from $276 in 2023 to $1,099 in 2024.
- 2023: $276
- 2024: $1,099
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Industry payments (Open Payments)
Industry payments (Open Payments) went from $326.47 in 2023 to $570.23 in 2025.
- 2023: $326.47
- 2024: $242.99
- 2025: $570.23
Sources: CMS Medicare Part D Prescribers (2024), CMS Open Payments (2025), CMS Doctors and Clinicians, CMS NPPES NPI Registry. Specialty names follow the NUCC Health Care Provider Taxonomy.
Text: T-MedInfo Β· Report an error.
Pharma & Medical Device Financial Disclosures
Payments and other transfers of value that drug and medical device companies reported to CMS Open Payments
Program year 2025 (payments made January 1 β December 31, 2025): 27 records totaling $570.23.
| Manufacturer | Payment Nature | Product | Type | Amount ($) |
|---|---|---|---|---|
| Janssen Pharmaceuticals, Inc |
Education
In-kind items and services
|
TREMFYA | General | $79.00 |
| Gilead Sciences, Inc. |
Food and Beverage
In-kind items and services
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β | General | $32.56 |
| Gilead Sciences, Inc. |
Food and Beverage
In-kind items and services
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β | General | $31.25 |
| Gilead Sciences, Inc. |
Food and Beverage
In-kind items and services
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β | General | $30.37 |
| Madrigal Pharmaceuticals |
Food and Beverage
In-kind items and services
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REZDIFFRA | General | $27.46 |
| Pfizer Inc. |
Food and Beverage
In-kind items and services
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VELSIPITY | General | $24.41 |
| ABBVIE INC. |
Food and Beverage
In-kind items and services
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LINZESS | General | $24.16 |
| Gilead Sciences, Inc. |
Food and Beverage
In-kind items and services
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β | General | $24.03 |
| Gilead Sciences, Inc. |
Food and Beverage
In-kind items and services
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β | General | $22.84 |
| Ardelyx, Inc. |
Food and Beverage
In-kind items and services
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IBSRELA | General | $21.76 |
| Azurity Pharmaceuticals, Inc. |
Food and Beverage
In-kind items and services
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SUFLAVE | General | $19.19 |
| Madrigal Pharmaceuticals |
Food and Beverage
In-kind items and services
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REZDIFFRA | General | $19.11 |
| ABBVIE INC. |
Food and Beverage
In-kind items and services
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CREON | General | $18.84 |
| Pfizer Inc. |
Food and Beverage
In-kind items and services
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XELJANZ | General | $17.78 |
| Intercept Pharmaceuticals, Inc. |
Food and Beverage
In-kind items and services
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OCALIVA | General | $17.62 |
| ABBVIE INC. |
Food and Beverage
In-kind items and services
|
CREON | General | $17.08 |
| Celltrion USA Inc. |
Food and Beverage
In-kind items and services
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VEGZELMA | General | $16.91 |
| ABBVIE INC. |
Food and Beverage
In-kind items and services
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LINZESS | General | $16.45 |
| Janssen Pharmaceuticals, Inc |
Food and Beverage
In-kind items and services
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TREMFYA | General | $16.40 |
| Janssen Pharmaceuticals, Inc |
Food and Beverage
In-kind items and services
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TREMFYA | General | $15.73 |
| Phathom Pharmaceuticals, Inc. |
Food and Beverage
Cash or cash equivalent
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VOQUEZNA | General | $15.04 |
| Phathom Pharmaceuticals, Inc. |
Food and Beverage
Cash or cash equivalent
|
VOQUEZNA | General | $14.68 |
| Pfizer Inc. |
Food and Beverage
In-kind items and services
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VELSIPITY | General | $13.78 |
| Janssen Pharmaceuticals, Inc |
Food and Beverage
In-kind items and services
|
TREMFYA | General | $10.42 |
| Janssen Pharmaceuticals, Inc |
Food and Beverage
In-kind items and services
|
TREMFYA | General | $9.16 |
(top 25 shown)
Source: CMS Open Payments, program year 2025, released June 30, 2026.
Medicare Part D Prescribing Profile & Medications
Medicare Part D prescriptions filled, including refills, in 2024.
| Brand Name | Generic Name | Prescriptions | Day Supply | Total Cost | Patients |
|---|---|---|---|---|---|
| Metoclopramide Hcl | Metoclopramide Hcl | 48 | 1,781 | $148.74 | 29 |
| Omeprazole | Omeprazole | 26 | 1,830 | $373.20 | 16 |
| Pantoprazole Sodium | Pantoprazole Sodium | 21 | 1,530 | $365.55 | 14 |
| Lansoprazole | Lansoprazole | 11 | 750 | $211.91 | β |
Source: CMS Part D by Provider and Drug, 2024; rows below 11 claims omitted by CMS; volume isn’t quality. Privacy limits
Specialties & License Numbers Reported to NPPES
Self-certified to NPPES: 2025-11-20NUCC Taxonomy Code: 363A00000X
A physician assistant is a person who has successfully completed an accredited education program for physician assistant, is licensed by the state and is practicing within the scope of that license. Physician assistants are formally trained to perform many of the routine, time-consuming tasks a physician can do. In some states, they may prescribe medications. They take medical histories, perform physical exams, order lab tests and x-rays, and give inoculations. Most states require that they work under the supervision of a physician.
Medicare (PECOS) Enrollment & Ordering Eligibility
Source: CMS PECOSPRACTITIONER - PHYSICIAN ASSISTANT
I20250820004645
IL
9335649722
Sources: CMS Provider Enrollment and Order and Referring. Medicare enrollment is a billing status, not an accreditation or quality rating.
Medicare Group Practice Enrollments
Source: CMS Doctors and Clinicians National Downloadable File
Illinois Gastroenterology Group Llc
745 Fletcher Dr, Elgin, IL 601234749
Phone: 8478881300
Illinois Gastroenterology Group Llc
1415 S Arlington Heights Rd, Arlington Heights, IL 600053765
Phone: 8476607755
Illinois Gastroenterology Group Llc
331 W Surf St, Chicago, IL 606577227
Illinois Gastroenterology Group Llc
800 Austin St, Evanston, IL 602023444
Phone: 8474919020
Secondary Practice Locations
800 Austin St
Evanston, IL 602023439
Phone: 8474919020
Clinicians Sharing This Practice Address or Phone
Clinicians sharing this NPPES address, phone or fax; a shared contact does not mean they work together.
Internal Medicine - Gastroenterology
Doctor of Medicine (M.D.)
Internal Medicine - Gastroenterology
Doctor of Osteopathic Medicine (D.O.)
Internal Medicine - Gastroenterology
Doctor of Medicine (M.D.)
Career & Practice History Timeline
Changes recorded in monthly NPPES data files: addresses, names, credentials, specialties and NPI status
Registered at 331 W SURF ST STE 912, CHICAGO, IL 606577227 (Tel: 8474919020)
Registered at 331 W SURF ST STE 912, CHICAGO, IL 606577227
Physician Assistant (license number reported to NPPES: IL 085009578)
Registered at 3517 N RACINE AVE, CHICAGO, IL 606571527 (Tel: 2624163638)
NPI status registered as active in NPPES database
Registered at 507 N 17TH STREET, MILWAUKEE, WI 53233 (Tel: 2624163638)
Registered at 507 N 17TH STREET, MILWAUKEE, WI 53233
Recorded as LILLIE COOK
Student in an Organized Health Care Education/Training Program
First registered as active Individual Practitioner in NPPES Database.
NPI Administrative Meta
Other Physician Assistants in Chicago
- Mary Schaefer, PA-C
- Ling Hua, PA-C
- Erica Blankemeyer, PA-C
- Lamija Hubjer, PA-C, MMS
- Peter Lopez, PA-C
- Ellen Sanders, PA-C
Mailing Address
331 W Surf St Ste 912
Chicago, IL 606577227