Ecopipam Tablets to Study Tourette's Syndrome in Children and Adolescents (opens in a new tab)
CompletedPhase 2
Tic DisordersTourette SyndromeEcopipam
Dr. John Gregory Duffy, MD
NPI1255497251
- Medicare services, 2021
- 71
- Part D claims, 2024
- 107
- Clinical trials
- 24
- Industry payments
- $8,218
- State license
- 1
- Practice address
- 11800 S 75th Ave, Palos Heights, IL 60463
- Practice phone
- Call (714) 542-3008
- Professional email
- Get professional email
- Personal email
- Get personal email
- Mobile number
- Get mobile number
Find Dr. Duffy'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. John Gregory Duffy is a psychiatrist in Palos Heights, Illinois
Dr. Duffy practices in Palos Heights, Illinois.
Dr. Duffy's NPI, 1255497251, was assigned on December 28, 2006. Dr. Duffy graduated from Georgetown University School Of Medicine in 1994. Dr. Duffy's California license number on file is A54948.
NPI and contact details
- NPI
- 1255497251NPI Registry (opens in a new tab)
- NPI enumeration date
- December 28, 2006
- NPI status
- Active
- Practice phone
- (714) 542-3008
- Professional email
- Get email
- Personal email
- Get email
- Mobile number
- Get number
- Sex
- Male
- Estimated age
- 58
- Medical school graduation
- 1994
Sources: NPPES NPI Registry (CMS); and Dmand AI Professional Profile Data
Dr. John Gregory Duffy's practice address is in Palos Heights, Illinois
Dr. Duffy's practice address in the NPI Registry is 11800 S 75th Ave, Palos Heights, IL 60463, in Cook County. The practice phone is (714) 542-3008.
- NPI Registry address11800 S 75th Ave, Palos Heights, IL 60463 · Cook CountyPhone(714) 542-3008
Sources: NPPES NPI Registry (CMS); and Dmand AI Practice Data
Dmand AI tracks the EHR system at Dr. John Gregory Duffy's practice
Dmand AI tracks the electronic health record (EHR) system at each site where Dr. Duffy practices. Vendor and product names are available with a free account.
| Site | EHR vendor and product |
|---|---|
| Dr. Duffy's practice | Available with a free account |
Source: Dmand AI Technology Install Data
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Dr. John Gregory Duffy is one of 1,527 psychiatrists in Illinois
Psychiatry is Dr. Duffy's primary specialty in the NPI Registry, under taxonomy code 2084P0800X. Dr. Duffy has a license on file in California.
Specialties and state licenses
- Psychiatry, CaliforniaPrimary
Clinical focus
Dmand AI lists bipolar disorder, depression, insomnia, non-alzheimer's dementia (chronic) and schizophrenia among the conditions Dr. Duffy treats.
Psychiatrists near Dr. Duffy
Counts of psychiatrists with a Dmand AI profile, by place and practice. Each opens the list.
1,527psychiatrists in Illinois
9psychiatrists in Palos Heights
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; and Dmand AI Peer Benchmarks
Dr. John Gregory Duffy billed Medicare for 71 services in 2021
CMS data shows 71 Medicare services from Dr. Duffy across 2 procedure codes in 2021, all of them office visits. Medicare paid $8,896 for them. Every service was in an office.
Medicare services, 202171
Paid by Medicare$8,896
Procedure codes2
Dr. Duffy's Medicare services by type, 2020 to 2021
- 2020
- 2021
- Office and hospital visits
- 2020: 1252021: 7143%
- Tests and treatments
- 2020: 992021: 0100%
Dr. Duffy compared with the Illinois median for psychiatrists, 2021
- Dr. Duffy
- Illinois median
- Medicare services
- 71vs 20365% below
- Part D claims
- 72vs 17459% below
Medians across 1,588 psychiatrists in Illinois with Dmand AI profiles that report each measure.
Dr. Duffy's most billed Medicare procedure codes, 2021
CMS publishes codes billed for 11 or more Medicare patients. Each label is the code family; CPT descriptions are licensed by the AMA.
Need commercial claims for Dr. Duffy?
Medicare shows one payer. Book a meeting to get commercial claims data for Dr. Duffy and other psychiatrists in Illinois.
Sources: Medicare Physician & Other Practitioners - by Provider and Service (CMS), 2024 data; and Dmand AI Peer Benchmarks
Dr. John Gregory Duffy's patients have a median age of 48
Across all payers, Dmand AI patient panel data puts Dr. Duffy's median patient age at 48, with 0% women.
Dr. Duffy's patients across all payers
Dmand AI patient panel data covers Medicare, Medicaid and commercial patients.
Patient panel by age, all payers
Median age 48
Patient panel by sex, all payers
- Women0%
- Men100%
Source: Dmand AI Patient Panel Data
Dr. John Gregory Duffy wrote 107 Medicare Part D claims in 2024
In 2024, Dr. Duffy wrote 107 Medicare Part D claims. 98% of them were for generic drugs. CMS names the drug for 72 of them, across 5 drugs with 11 or more claims each, at $1,202 in total drug cost. In 2023, CMS named 180 claims across 10 drugs.
Part D claims, 2024107
Drugs named by CMS5
Total drug cost$1,202
Dr. Duffy's Part D claims by kind of drug, 2024
- Generic105 claims98%
- Brand-name and other2 claims2%
Dr. Duffy'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. Duffy's Part D claims, 2024
- Antipsychotics, patients 65 and over11%12 of 107 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: 1802024: 7260%
Drugs named by CMS: 5 in 2024, 10 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
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Dr. John Gregory Duffy has worked on 24 clinical trials
Dmand AI links Dr. Duffy to 24 clinical trials, 3 of them phase 2 studies. 3 are still active or recruiting. Conditions studied include Alzheimer Disease, Tauopathies and Binge-Eating Disorder. Eli Lilly and Company sponsors the most, 8. Open Payments lists research payments to Dr. Duffy that name 16 trials.
Clinical trials with Dr. Duffy by phase
- NonePhase 1: no trials
- 1Phase 1/2: 1 trial
- 3Phase 2: 3 trials
- 2Phase 2/3: 2 trials
- 2Phase 3: 2 trials
- NonePhase 4: no trials
Conditions in Dr. Duffy's trials
- Alzheimer Disease
- Tauopathies
- Binge-Eating Disorder
- Cognition Disorders
- Cognitive Dysfunction
Investigators on the most trials with Dr. Duffy
Recent clinical trials with Dr. Duffy
GAIN Trial: Phase 2/3 Study of COR388 in Subjects With Alzheimer's Disease (opens in a new tab)
CompletedPhase 2/3
Alzheimer DiseaseTauopathiesCOR388 capsule
Alzheimer DiseaseTauopathiesFlortaucipir F18
A Study to Evaluate the Safety and Efficacy of AstroStem in Treatment of Alzheimer's Disease (opens in a new tab)
CompletedPhase 1/2
Alzheimer DiseaseTauopathiesAstroStem
Memory Improvement Through Nicotine Dosing (MIND) Study (opens in a new tab)
Active, not recruitingPhase 2
Cognitive DysfunctionCognition DisordersNicotine Transdermal Patch
Sources: ClinicalTrials.gov (National Library of Medicine); and Dmand AI Research Linkage
Dr. John Gregory Duffy received $8,218 in industry payments from 2016 to 2025
CMS Open Payments shows 31 general payments to Dr. Duffy from 6 drug and device companies from 2016 to 2025. Travel and lodging make up the largest share, 53% of the total. Eli Lilly and Company paid the most, $5,356. It also lists 201 research payments totaling $255,399 from 2016 to 2025, naming 16 clinical trials.
General payments to Dr. Duffy by program year, 2016 to 2025
General payments to Dr. Duffy by kind, 2016 to 2025
$8.2Kin total
- Travel and lodging$4,38853%
- Consulting fees$2,10026%
- Food and beverage$1,64420%
- Education$761%
- Gifts$100%
Companies that paid Dr. Duffy the most, 2016 to 2025
Share is of all general payments to this clinician.
Source: Open Payments (CMS), 2025 data, released July 7, 2026
Dr. John Gregory Duffy graduated from Georgetown University School Of Medicine
Dr. Duffy graduated from Georgetown University School Of Medicine in 1994.
- Medical school
Source: Dmand AI Professional Profile Data
Sources for Dr. John Gregory Duffy'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 |
| 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 Data |
| 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) |
| Clinical trials and co-investigators | ClinicalTrials.gov (National Library of Medicine) (opens in a new tab)Dmand AI Research Linkage |
| 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. John Gregory Duffy
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. John Gregory Duffy's NPI number?
Dr. John Gregory Duffy's NPI number is 1255497251. It was assigned on December 28, 2006, and it is active in the NPI Registry.
What kind of doctor is Dr. John Gregory Duffy?
Dr. John Gregory Duffy is a psychiatrist in Palos Heights, Illinois. The primary specialty in the NPI Registry is Psychiatry Physician (taxonomy code 2084P0800X).
Where does Dr. John Gregory Duffy practice?
Dr. Duffy practices at 11800 S 75th Ave, Palos Heights, IL 60463.
What is Dr. John Gregory Duffy's office phone number?
The practice phone on file for Dr. Duffy is (714) 542-3008.
What is Dr. John Gregory Duffy's medical license number?
Dr. Duffy's California license number on file is A54948.
Does Dr. John Gregory Duffy accept Medicare?
Yes. CMS data shows Dr. Duffy billed Medicare for 71 services in 2021.
What services does Dr. John Gregory Duffy bill to Medicare?
In 2021, Dr. Duffy's most billed Medicare services were office visit, established patient (99214) and office visit, established patient (99215).
Where did Dr. John Gregory Duffy go to medical school?
Dr. Duffy graduated from Georgetown University School Of Medicine in 1994.
What drugs does Dr. John Gregory Duffy prescribe most?
In 2024 Medicare Part D data, Dr. Duffy's most prescribed drugs by claims were Bupropion XL, Divalproex Sodium ER and Escitalopram Oxalate.
Has Dr. John Gregory Duffy received payments from drug or device companies?
CMS Open Payments shows $8,218 in general payments to Dr. Duffy from 6 companies from 2016 to 2025. The largest total came from Eli Lilly and Company.
How long has Dr. John Gregory Duffy been practicing?
Dr. Duffy graduated from medical school in 1994, 32 years ago.
Does Dr. John Gregory Duffy do research?
Dr. Duffy has worked on 24 clinical trials.
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