Dr. Michael James Brennan, DO, MPH
- Medicare services, 2024
- 50
- Medicare patients, 2024
- 66
- Part D claims, 2024
- 51
- Hospital affiliations
- 5
- Industry payments
- $305
- Practice address
- 4440 W 95th Street, Oak Lawn, IL 60453
- Practice phone
- Call (708) 684-8000
- Professional email
- Get professional email
- Personal email
- Get personal email
- Mobile number
- Get mobile number
Primary practice
Find Dr. Brennan'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. Michael James Brennan is an emergency medicine physician in Oak Lawn, Illinois
Dr. Brennan practices at Advocate Christ Medical Center in Oak Lawn, Illinois, part of Advocate Health.
Dr. Brennan's NPI, 1811550981, was assigned on April 15, 2019. Dr. Brennan graduated from Lake Erie Col of Osteopathic Medicine, Bradenton in 2019. Dr. Brennan holds Illinois license 036.164300.
- NPI
- 1811550981NPI Registry (opens in a new tab)
- Medicare PAC ID
- 4587998208
- NPI enumeration date
- April 15, 2019
- NPI status
- Active
- Accepts Medicare assignment
- Yes
- Practice phone
- (708) 684-8000
- Professional email
- Get email
- Personal email
- Get email
- Mobile number
- Get number
- Sex
- Male
- Estimated age
- 33
- Medical school graduation
- 2019
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; Dmand AI Affiliation Data; and Doctors and Clinicians National Downloadable File (CMS)
Dr. Michael James Brennan practices at Advocate Christ Medical Center in Oak Lawn, Illinois
Dr. Brennan's primary practice is Advocate Christ Medical Center, at 4440 W 95th Street, Oak Lawn, IL 60453 in Cook County. The practice phone is (708) 684-8000.
- Advocate Christ Medical Center4440 W 95th Street, Oak Lawn, IL 60453 · Cook CountyPhone(708) 684-8000
Source: Dmand AI Affiliation Data
Dr. Michael James Brennan is affiliated with 10 sites of care and 12 medical groups
Dr. Brennan's primary practice is Advocate Christ Medical Center in Oak Lawn, Illinois, part of Advocate Health. Dr. Brennan is also affiliated with Advocate Trinity Hospital. The medical group on file is Dreyer Medical Clinic (Advocate Medical Group). Dmand AI also links Dr. Brennan to 3 more hospitals, 11 medical groups, 4 group practices and clinics and 1 hospice, each named with a free account.
Sources: Dmand AI Affiliation Data; and Dmand AI Org Hierarchy Data
Dmand AI tracks the EHR system at Dr. Michael James Brennan's practice
Dmand AI tracks the electronic health record (EHR) system at each site where Dr. Brennan practices, 10 sites in all. Vendor and product names are available with a free account.
| Site | EHR vendor and product |
|---|---|
| Advocate Christ Medical Center | Available with a free account |
| +9 more sites and 11 medical groups | Available with a free account |
Source: Dmand AI Technology Install Data
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Dr. Michael James Brennan is one of 2,385 emergency medicine physicians in Illinois
Emergency medicine is Dr. Brennan's primary specialty in the NPI Registry, under taxonomy code 207P00000X. Dmand AI has Dr. Brennan's licenses on file in 2 states: Illinois and Michigan.
Specialties and state licenses
- Emergency medicine, IllinoisPrimary
- Michigan license
Emergency medicine physicians near Dr. Brennan
Counts of emergency medicine physicians 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. Michael James Brennan billed Medicare for 50 services in 2024
CMS data shows 50 Medicare services from Dr. Brennan across 2 procedure codes in 2024, for 66 Medicare patients. Medicare paid $5,712 for them. Every service was in a facility, such as a hospital, rather than an office.
Dr. Brennan's Medicare services by type, 2023 to 2024
- 2023
- 2024
- Office and hospital visits
- 2023: 232024: 50117%
Dr. Brennan compared with the Illinois median for emergency medicine physicians, 2024
- Dr. Brennan
- Illinois median
- Medicare services
- 50vs 27482% below
- Medicare patients
- 66vs 27376% below
- Part D claims
- 38vs 4516% below
Medians across 2,281 emergency medicine physicians in Illinois with Dmand AI profiles that report each measure.
Dr. Brennan'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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Sources: Medicare Physician & Other Practitioners - by Provider and Service (CMS), 2024 data; and Dmand AI Peer Benchmarks
Dr. Michael James Brennan treated 66 Medicare patients in 2024, average age 74
CMS counts 66 Medicare patients who saw Dr. Brennan in 2024. The largest group is 65 to 74, with 23 patients. 75% of them have high blood pressure, and 75% have high cholesterol. 42% are also on Medicaid. Their average risk score is 2.80, 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. Brennan's median patient age at 70, with 54% women.
Dr. Brennan's Medicare patients by age, 2024
Dr. Brennan's Medicare patients by sex, 2024
- Women4264%
- Men2436%
Chronic conditions among Dr. Brennan's Medicare patients, 2024
- High blood pressure75%
- High cholesterol75%
- Diabetes59%
- Ischemic heart disease59%
- Arthritis58%
- Chronic kidney disease45%
- Heart failure42%
- Anxiety36%
Share of Medicare patients with each condition. A patient can have several.
Dr. Brennan's patients across all payers
Dmand AI patient panel data covers Medicare, Medicaid and commercial patients.
Patient panel by age, all payers
Median age 70
Patient panel by sex, all payers
- Women54%
- Men46%
Sources: Dmand AI Patient Panel Data; and Medicare Physician & Other Practitioners - by Provider (CMS), 2024 data
Dr. Michael James Brennan wrote 51 Medicare Part D claims in 2024
In 2024, Dr. Brennan wrote 51 Medicare Part D claims for 38 patients. 96% of them were for generic drugs. CMS names the drug for 38 of them, across 2 drugs with 11 or more claims each, at $123 in total drug cost. In 2022, CMS named 36 claims across 2 drugs.
Dr. Brennan's Part D claims by kind of drug, 2024
- Generic49 claims96%
- Brand-name and other2 claims4%
Dr. Brennan's most prescribed drugs by claims, 2023
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. Brennan's Part D claims, 2024
- Antibiotics25%13 of 51 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, 2022 to 2023
- 2022
- 2023
- Claims for drugs CMS names
- 2022: 362023: 386%
Drugs named by CMS: 2 in 2023, 2 in 2022.
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
How Dr. Michael James Brennan takes part in Medicare
Dr. Brennan accepts Medicare assignment, so Medicare's approved amount is taken as full payment.
- Accepts Medicare assignment
- Yes
Source: Doctors and Clinicians National Downloadable File (CMS)
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Dr. Michael James Brennan received $305 in industry payments from 2020 to 2025
CMS Open Payments shows 6 general payments to Dr. Brennan from 5 drug and device companies from 2020 to 2025. Food and beverage make up the largest share, 100% of the total. Bristol-Myers Squibb Company paid the most, $125.
General payments to Dr. Brennan by program year, 2020 to 2025
Companies that paid Dr. Brennan the most, 2020 to 2025
Share is of all general payments to this clinician.
Source: Open Payments (CMS), 2025 data, released July 7, 2026
Dr. Michael James Brennan graduated from Lake Erie Col of Osteopathic Medicine, Bradenton
Dr. Brennan graduated from Lake Erie Col of Osteopathic Medicine, Bradenton in 2019.
- Medical school
Source: Dmand AI Professional Profile Data
Sources for Dr. Michael James Brennan'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 | Dmand AI Affiliation Data |
| Primary practice, affiliations and health system | Dmand 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. Michael James Brennan
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. Michael James Brennan's NPI number?
Dr. Michael James Brennan's NPI number is 1811550981. It was assigned on April 15, 2019, and it is active in the NPI Registry.
What kind of doctor is Dr. Michael James Brennan?
Dr. Michael James Brennan is an emergency medicine physician in Oak Lawn, Illinois. The primary specialty in the NPI Registry is Emergency Medicine Physician (taxonomy code 207P00000X).
Where does Dr. Michael James Brennan practice?
Dr. Brennan practices at 4440 W 95th Street, Oak Lawn, IL 60453. Dr. Brennan's primary practice is Advocate Christ Medical Center in Oak Lawn, Illinois, part of Advocate Health. Dmand AI also links Dr. Brennan to 3 hospitals, 11 medical groups, 4 group practices and clinics and 1 hospice.
What is Dr. Michael James Brennan's office phone number?
The practice phone on file for Dr. Brennan is (708) 684-8000.
What is Dr. Michael James Brennan's medical license number?
Dr. Brennan holds Illinois license 036.164300, one of the licenses on file in 2 states.
Which states has Dr. Michael James Brennan been licensed in?
Dmand AI has state licenses on file for Dr. Brennan in Illinois and Michigan.
Which hospitals is Dr. Michael James Brennan affiliated with?
Dr. Brennan practices at Advocate Christ Medical Center in Oak Lawn, Illinois. Dr. Brennan is also affiliated with Advocate Trinity Hospital. Dmand AI links Dr. Brennan to 3 more hospitals.
What medical group is Dr. Michael James Brennan part of?
Dr. Brennan is linked to Dreyer Medical Clinic (Advocate Medical Group). Dmand AI links Dr. Brennan to 11 more medical groups.
Does Dr. Michael James Brennan accept Medicare?
Yes. CMS data shows Dr. Brennan billed Medicare for 50 services in 2024, and Dr. Brennan accepts Medicare assignment.
How many Medicare patients does Dr. Michael James Brennan see?
CMS counts 66 Medicare patients who saw Dr. Brennan in 2024, with an average age of 74.
Show 5 more questionsShow fewer questions
What services does Dr. Michael James Brennan bill to Medicare?
In 2024, Dr. Brennan's most billed Medicare services were emergency department visit (99285) and emergency department visit (99284).
Where did Dr. Michael James Brennan go to medical school?
Dr. Brennan graduated from Lake Erie Col of Osteopathic Medicine, Bradenton in 2019.
What drugs does Dr. Michael James Brennan prescribe most?
In 2023 Medicare Part D data, Dr. Brennan's most prescribed drugs by claims were Ibuprofen and Methocarbamol.
Has Dr. Michael James Brennan received payments from drug or device companies?
CMS Open Payments shows $305 in general payments to Dr. Brennan from 5 companies from 2020 to 2025. The largest total came from Bristol-Myers Squibb Company.
How long has Dr. Michael James Brennan been practicing?
Dr. Brennan graduated from medical school in 2019, 7 years ago.
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