Dr. Mai-Sie F. Chan, MD
- Medicare services, 2024
- 1,160
- Medicare patients, 2024
- 138
- Part D claims, 2024
- 5,588
- Hospital affiliations
- 3
- Industry payments
- $546
- Practice address
- 929 Clay St Ste 303, San Francisco, CA 94108-1570
- Practice phone
- Call (415) 956-6633
- Professional email
- Get professional email
- Personal email
- Get personal email
- Mobile number
- Get mobile number
Primary practice
Mai-Sie Chan, M.D., Inc
Physician office · San Francisco, California
Find Dr. Chan's professional email, personal email and mobile number
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Dr. Mai-Sie F. Chan is an internist in San Francisco, California
Dr. Chan practices at Mai-Sie Chan, M.D., Inc in San Francisco, California.
Dr. Chan's NPI, 1326136557, was assigned on October 11, 2006. Dr. Chan graduated from Stanford University School of Medicine in 2001. Dr. Chan holds California license A83362.
- NPI
- 1326136557NPI Registry (opens in a new tab)
- Medicare PAC ID
- 4183603848
- NPI enumeration date
- October 11, 2006
- NPI status
- Active
- Accepts Medicare assignment
- Yes
- Offers telehealth
- Yes
- Practice phone
- (415) 956-6633
- Professional email
- Get email
- Personal email
- Get email
- Mobile number
- Get number
- Sex
- Female
- Estimated age
- 51
- Medical school graduation
- 2001
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; Dmand AI Affiliation Data; and Doctors and Clinicians National Downloadable File (CMS)
Dr. Mai-Sie F. Chan practices at Mai-Sie Chan, M.D., Inc in San Francisco, California
Dr. Chan's primary practice is Mai-Sie Chan, M.D., Inc, at 929 Clay St Ste 303, San Francisco, CA 94108-1570. The practice phone is (415) 956-6633.
- Mai-Sie Chan, M.D., Inc929 Clay St Ste 303, San Francisco, CA 94108-1570Phone(415) 956-6633
Source: Dmand AI Affiliation Data
Dr. Mai-Sie F. Chan is affiliated with 5 sites of care
Dr. Chan's primary practice is Mai-Sie Chan, M.D., Inc in San Francisco, California. Dr. Chan is also affiliated with California Pacific Medical Center Van Ness Campus. Dmand AI also links Dr. Chan to 2 more hospitals and 1 home health agency, each named with a free account.
Source: Dmand AI Affiliation Data
Dmand AI tracks the EHR system at Dr. Mai-Sie F. Chan's practice
Dmand AI tracks the electronic health record (EHR) system at each site where Dr. Chan practices, 5 sites in all. Vendor and product names are available with a free account.
| Site | EHR vendor and product |
|---|---|
| Mai-Sie Chan, M.D., Inc | Available with a free account |
| +4 more affiliated sites | Available with a free account |
Source: Dmand AI Technology Install Data
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Dr. Mai-Sie F. Chan is one of 16,751 internists in California
Internal medicine is Dr. Chan's primary specialty in the NPI Registry, under taxonomy code 207R00000X. Dr. Chan is licensed in California.
Specialties and state licenses
- Internal medicine, CaliforniaPrimary
Internists near Dr. Chan
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. Mai-Sie F. Chan billed Medicare for 1,160 services in 2024
CMS data shows 1,160 Medicare services from Dr. Chan across 7 procedure codes in 2024, for 138 Medicare patients. Medicare paid $76,093 for them. Every service was in an office.
Dr. Chan's Medicare services by type, 2023 to 2024
- 2023
- 2024
- Other services
- 2023: 1692024: 578242%
- Office and hospital visits
- 2023: 5112024: 5061%
- Tests and treatments
- 2023: 912024: 7616%
Dr. Chan compared with the California median for internists, 2024
- Dr. Chan
- California median
- Medicare services
- 1,160vs 3613.2 times
- Medicare patients
- 138vs 1519% below
- Part D claims
- 5,015vs 42111.9 times
Medians across 15,815 internists in California with Dmand AI profiles that report each measure.
Dr. Chan'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. Mai-Sie F. Chan treated 138 Medicare patients in 2024, average age 79
CMS counts 138 Medicare patients who saw Dr. Chan in 2024. The largest group is 75 to 84, with 52 patients. 75% of them have high blood pressure, and 75% have high cholesterol. 85% are also on Medicaid. Their average risk score is 1.29, where 1.00 is the Medicare average.
Across all payers, Dmand AI patient panel data puts Dr. Chan's median patient age at 72, with 66% women.
Dr. Chan's Medicare patients by age, 2024
CMS leaves out age groups with fewer than 11 patients.
Dr. Chan's Medicare patients by sex, 2024
- Women10173%
- Men3727%
Chronic conditions among Dr. Chan's Medicare patients, 2024
- High blood pressure75%
- High cholesterol75%
- Arthritis44%
- Diabetes36%
- Chronic kidney disease30%
- Alzheimer's and dementia18%
- Mood disorders14%
- Osteoporosis14%
Share of Medicare patients with each condition. A patient can have several.
Dr. Chan's patients across all payers
Dmand AI patient panel data covers Medicare, Medicaid and commercial patients.
Patient panel by age, all payers
Median age 72
Patient panel by sex, all payers
- Women66%
- Men27%
Sources: Dmand AI Patient Panel Data; and Medicare Physician & Other Practitioners - by Provider (CMS), 2024 data
Dr. Mai-Sie F. Chan wrote 5,588 Medicare Part D claims in 2024
In 2024, Dr. Chan wrote 5,588 Medicare Part D claims for 398 patients. 88% of them were for generic drugs. CMS names the drug for 5,015 of them, across 85 drugs with 11 or more claims each, at $563,387 in total drug cost. In 2023, CMS named 4,596 claims across 77 drugs.
Dr. Chan's Part D claims by kind of drug, 2024
- Generic4,894 claims88%
- Brand-name656 claims12%
- Other38 claims1%
Dr. Chan'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. Chan's Part D claims, 2024
- Opioids0%16 of 5,588 claims
- Antibiotics1%48 of 5,588 claims
- Antipsychotics, patients 65 and over0%20 of 5,588 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: 4,5962024: 5,0159%
Drugs named by CMS: 85 in 2024, 77 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. Mai-Sie F. Chan offers telehealth to Medicare patients
Dr. Chan accepts Medicare assignment, so Medicare's approved amount is taken as full payment. CMS lists Dr. Chan as offering telehealth.
- Accepts Medicare assignment
- Yes
- Offers telehealth
- Yes
Source: Doctors and Clinicians National Downloadable File (CMS)
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Dr. Mai-Sie F. Chan received $546 in industry payments from 2016 to 2019
CMS Open Payments shows 9 general payments to Dr. Chan from 5 drug and device companies from 2016 to 2019. Food and beverage make up the largest share, 100% of the total. Janssen Pharmaceuticals, Inc paid the most, $171.
General payments to Dr. Chan by program year, 2016 to 2019
Companies that paid Dr. Chan the most, 2016 to 2019
Share is of all general payments to this clinician.
Source: Open Payments (CMS), 2025 data, released July 7, 2026
Dr. Mai-Sie F. Chan graduated from Stanford University School of Medicine
Dr. Chan graduated from Stanford University School of Medicine in 2001.
- Medical school
Source: Dmand AI Professional Profile Data
Sources for Dr. Mai-Sie F. Chan'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 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. Mai-Sie F. Chan
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. Mai-Sie F. Chan's NPI number?
Dr. Mai-Sie F. Chan's NPI number is 1326136557. It was assigned on October 11, 2006, and it is active in the NPI Registry.
What kind of doctor is Dr. Mai-Sie F. Chan?
Dr. Mai-Sie F. Chan is an internist in San Francisco, California. The primary specialty in the NPI Registry is Internal Medicine Physician (taxonomy code 207R00000X).
Where does Dr. Mai-Sie F. Chan practice?
Dr. Chan practices at 929 Clay St Ste 303, San Francisco, CA 94108-1570. Dr. Chan's primary practice is Mai-Sie Chan, M.D., Inc in San Francisco, California. Dmand AI also links Dr. Chan to 2 hospitals and 1 home health agency.
What is Dr. Mai-Sie F. Chan's office phone number?
The practice phone on file for Dr. Chan is (415) 956-6633.
What is Dr. Mai-Sie F. Chan's medical license number?
Dr. Chan holds California license A83362.
Which hospitals is Dr. Mai-Sie F. Chan affiliated with?
Dr. Chan is affiliated with California Pacific Medical Center Van Ness Campus. Dmand AI links Dr. Chan to 2 more hospitals.
Does Dr. Mai-Sie F. Chan accept Medicare?
Yes. CMS data shows Dr. Chan billed Medicare for 1,160 services in 2024, and Dr. Chan accepts Medicare assignment.
Does Dr. Mai-Sie F. Chan offer telehealth?
Yes. The CMS Doctors and Clinicians file lists Dr. Chan as offering telehealth services.
How many Medicare patients does Dr. Mai-Sie F. Chan see?
CMS counts 138 Medicare patients who saw Dr. Chan in 2024, with an average age of 79.
What services does Dr. Mai-Sie F. Chan bill to Medicare?
In 2024, Dr. Chan's most billed Medicare services were office visit, established patient (99214), medicare service (G2211) and office visit, established patient (99213).
Show 4 more questionsShow fewer questions
Where did Dr. Mai-Sie F. Chan go to medical school?
Dr. Chan graduated from Stanford University School of Medicine in 2001.
What drugs does Dr. Mai-Sie F. Chan prescribe most?
In 2024 Medicare Part D data, Dr. Chan's most prescribed drugs by claims were Losartan Potassium, Atorvastatin Calcium and Amlodipine Besylate.
Has Dr. Mai-Sie F. Chan received payments from drug or device companies?
CMS Open Payments shows $546 in general payments to Dr. Chan from 5 companies from 2016 to 2019. The largest total came from Janssen Pharmaceuticals, Inc.
How long has Dr. Mai-Sie F. Chan been practicing?
Dr. Chan graduated from medical school in 2001, 25 years ago.
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