Dr. Patrick S. Chang, MD
- Medicare services, 2019
- 586
- Part D claims, 2019
- 1,352
- Hospital affiliations
- 1
- Industry payments
- $2,464
- Medical group
- 1
- Practice address
- 757 Westwood Plaza, Los Angeles, CA 90095
- Practice phone
- Call (310) 825-6301
- Professional email
- Get professional email
- Personal email
- Get personal email
- Mobile number
- Get mobile number
Primary practice
Find Dr. Chang'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. Patrick S. Chang is an internist in Los Angeles, California
Dr. Chang practices at Ronald Reagan UCLA Medical Center in Los Angeles, California, part of University of California Health.
Dr. Chang's NPI, 1861467656, was assigned on February 23, 2006. Dr. Chang holds Arizona license 21908.
- NPI
- 1861467656NPI Registry (opens in a new tab)
- NPI enumeration date
- February 23, 2006
- NPI status
- Active
- Practice phone
- (310) 825-6301
- Professional email
- Get email
- Personal email
- Get email
- Mobile number
- Get number
- Sex
- Male
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; and Dmand AI Affiliation Data
Dr. Patrick S. Chang practices at Ronald Reagan UCLA Medical Center in Los Angeles, California
Dr. Chang's primary practice is Ronald Reagan UCLA Medical Center, at 757 Westwood Plaza, Los Angeles, CA 90095 in Los Angeles County. The practice phone is (310) 825-6301.
- Ronald Reagan UCLA Medical Center757 Westwood Plaza, Los Angeles, CA 90095 · Los Angeles CountyPhone(310) 825-6301
Source: Dmand AI Affiliation Data
Dr. Patrick S. Chang is affiliated with 2 sites of care and 1 medical group
Dr. Chang's primary practice is Ronald Reagan UCLA Medical Center in Los Angeles, California, part of University of California Health. Dmand AI also links Dr. Chang to 1 group practice or clinic and 1 medical group, 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. Patrick S. Chang's practice
Dmand AI tracks the electronic health record (EHR) system at each site where Dr. Chang practices, 2 sites in all. Vendor and product names are available with a free account.
| Site | EHR vendor and product |
|---|---|
| Ronald Reagan UCLA Medical Center | Available with a free account |
| +1 more site and 1 medical group | Available with a free account |
Source: Dmand AI Technology Install Data
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Dr. Patrick S. Chang is one of 16,751 internists in California
Internal medicine is Dr. Chang's primary specialty in the NPI Registry, under taxonomy code 207R00000X. Dr. Chang is licensed in Arizona.
Specialties and state licenses
- Internal medicine, ArizonaPrimary
Internists near Dr. Chang
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. Patrick S. Chang billed Medicare for 586 services in 2019
CMS data shows 586 Medicare services from Dr. Chang across 5 procedure codes in 2019. Medicare paid $24,155 for them. Every service was in an office.
Dr. Chang's Medicare services by type, 2018 to 2019
- 2018
- 2019
- Office and hospital visits
- 2018: 3,2792019: 47086%
- Drugs given in the office
- 2018: 6612019: 8587%
- Tests and treatments
- 2018: 2,1172019: 3199%
- Other services
- 2018: 5172019: 0100%
- Surgery
- 2018: 3922019: 0100%
Dr. Chang compared with the California median for internists, 2019
- Dr. Chang
- California median
- Medicare services
- 586vs 36162% above
- Part D claims
- 1,352vs 4213.2 times
Medians across 15,815 internists in California with Dmand AI profiles that report each measure.
Dr. Chang's most billed Medicare procedure codes, 2019
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. Chang and other internists in California.
Sources: Medicare Physician & Other Practitioners - by Provider and Service (CMS), 2024 data; and Dmand AI Peer Benchmarks
Dr. Patrick S. Chang's patients have a median age of 66
Across all payers, Dmand AI patient panel data puts Dr. Chang's median patient age at 66, with 38% women.
Dr. Chang's patients across all payers
Dmand AI patient panel data covers Medicare, Medicaid and commercial patients.
Patient panel by age, all payers
Median age 66
Patient panel by sex, all payers
- Women38%
- Men60%
Source: Dmand AI Patient Panel Data
Dr. Patrick S. Chang wrote 1,352 Medicare Part D claims in 2019
In 2019, Dr. Chang wrote 1,352 Medicare Part D claims. They cover 42 drugs, with $29,497 in total drug cost. In 2018, CMS named 4,689 claims across 105 drugs.
Dr. Chang's most prescribed drugs by claims, 2019
CMS names a drug when it has 11 or more claims. Share is of the claims for drugs CMS names.
Part D claims for drugs CMS names, 2018 to 2019
- 2018
- 2019
- Claims for drugs CMS names
- 2018: 4,6892019: 1,35271%
Drugs named by CMS: 42 in 2019, 105 in 2018.
Source: Medicare Part D Prescribers - by Provider and Drug (CMS), 2024 data, released May 6, 2026
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Dr. Patrick S. Chang received $2,464 in industry payments from 2016 to 2022
CMS Open Payments shows 168 general payments to Dr. Chang from 23 drug and device companies from 2016 to 2022. Food and beverage make up the largest share, 99% of the total. GlaxoSmithKline, LLC. paid the most, $430.
General payments to Dr. Chang by program year, 2016 to 2022
General payments to Dr. Chang by kind, 2016 to 2022
- Food and beverage$2,43499%
- Education$301%
Companies that paid Dr. Chang the most, 2016 to 2022
Share is of all general payments to this clinician.
Source: Open Payments (CMS), 2025 data, released July 7, 2026
Sources for Dr. Patrick S. Chang'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 Data |
| Part D prescribing | Medicare Part D Prescribers - by Provider and Drug (CMS) (opens in a new tab) |
| Industry payments | Open Payments (CMS) (opens in a new tab) |
| 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. Patrick S. Chang
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. Patrick S. Chang's NPI number?
Dr. Patrick S. Chang's NPI number is 1861467656. It was assigned on February 23, 2006, and it is active in the NPI Registry.
What kind of doctor is Dr. Patrick S. Chang?
Dr. Patrick S. Chang is an internist in Los Angeles, California. The primary specialty in the NPI Registry is Internal Medicine Physician (taxonomy code 207R00000X).
Where does Dr. Patrick S. Chang practice?
Dr. Chang practices at 757 Westwood Plaza, Los Angeles, CA 90095. Dr. Chang's primary practice is Ronald Reagan UCLA Medical Center in Los Angeles, California, part of University of California Health. Dmand AI also links Dr. Chang to 1 group practice or clinic and 1 medical group.
What is Dr. Patrick S. Chang's office phone number?
The practice phone on file for Dr. Chang is (310) 825-6301.
What is Dr. Patrick S. Chang's medical license number?
Dr. Chang holds Arizona license 21908.
Which hospitals is Dr. Patrick S. Chang affiliated with?
Dr. Chang practices at Ronald Reagan UCLA Medical Center in Los Angeles, California.
Does Dr. Patrick S. Chang accept Medicare?
Yes. CMS data shows Dr. Chang billed Medicare for 586 services in 2019.
What services does Dr. Patrick S. Chang bill to Medicare?
In 2019, Dr. Chang's most billed Medicare services were office visit, established patient (99214), injected or infused drug (J3420) and office visit, established patient (99211).
What drugs does Dr. Patrick S. Chang prescribe most?
In 2019 Medicare Part D data, Dr. Chang's most prescribed drugs by claims were Levothyroxine Sodium, Atorvastatin Calcium and Metformin HCl.
Has Dr. Patrick S. Chang received payments from drug or device companies?
CMS Open Payments shows $2,464 in general payments to Dr. Chang from 23 companies from 2016 to 2022. The largest total came from GlaxoSmithKline, LLC.
How long has Dr. Patrick S. Chang been practicing?
Dr. Chang's NPI was assigned in 2006.
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