Dr. Ester C. Kwok, MD
- Medicare services, 2024
- 795
- Medicare patients, 2024
- 307
- Part D claims, 2024
- 3,097
- Hospital affiliations
- 4
- Industry payments
- $45
- Practice address
- 300 Pasteur Drive, Stanford, CA 94305
- Practice phone
- Call (650) 723-4000
- Professional email
- Get professional email
- Personal email
- Get personal email
- Mobile number
- Get mobile number
Primary practice
Find Dr. Kwok'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. Ester C. Kwok is an internist in Stanford, California
Dr. Kwok practices at Stanford Hospital at 300 Pasteur Drive in Stanford, California, part of Stanford University.
Dr. Kwok's NPI, 1790886034, was assigned on September 26, 2006. Dr. Kwok graduated from McGovern Medical School in 1989. Dr. Kwok's California license number on file is A050957.
- NPI
- 1790886034NPI Registry (opens in a new tab)
- Medicare PAC ID
- 6901978261
- NPI enumeration date
- September 26, 2006
- NPI status
- Active
- Accepts Medicare assignment
- Yes
- Offers telehealth
- Yes
- Practice phone
- (650) 723-4000
- Professional email
- Get email
- Personal email
- Get email
- Mobile number
- Get number
- Sex
- Female
- Estimated age
- 63
- Medical school graduation
- 1989
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; Dmand AI Affiliation Data; and Doctors and Clinicians National Downloadable File (CMS)
Dr. Ester C. Kwok practices at Stanford Hospital at 300 Pasteur Drive in Stanford, California
Dr. Kwok's primary practice is Stanford Hospital at 300 Pasteur Drive, at 300 Pasteur Drive, Stanford, CA 94305 in Santa Clara County. The practice phone is (650) 723-4000.
- Stanford Hospital at 300 Pasteur Drive300 Pasteur Drive, Stanford, CA 94305 · Santa Clara CountyPhone(650) 723-4000
Source: Dmand AI Affiliation Data
Dr. Ester C. Kwok is affiliated with 7 sites of care and 1 medical group
Dr. Kwok's primary practice is Stanford Hospital at 300 Pasteur Drive in Stanford, California, part of Stanford University. Dr. Kwok is also affiliated with El Camino Health - Mountain View Hospital. The medical group on file is El Camino Health Medical Network. Dmand AI also links Dr. Kwok to 2 more hospitals, 1 physician office, 1 group practice or clinic and 1 home health agency, 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. Ester C. Kwok's practice
Dmand AI tracks the electronic health record (EHR) system at each site where Dr. Kwok practices, 7 sites in all. Vendor and product names are available with a free account.
| Site | EHR vendor and product |
|---|---|
| Stanford Hospital at 300 Pasteur Drive | Available with a free account |
| +6 more affiliated sites | Available with a free account |
Source: Dmand AI Technology Install Data
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Dr. Ester C. Kwok is one of 16,751 internists in California
Internal medicine is Dr. Kwok's primary specialty in the NPI Registry, under taxonomy code 207R00000X. Dr. Kwok is board certified in internal medicine by the American Board of Internal Medicine. Dr. Kwok has a license on file in California.
Specialties and state licenses
- Internal medicine, CaliforniaPrimary
Clinical focus
Dmand AI lists acid reflux, acute gallbladder or bile duct inflammation, acute kidney failure, acute sinusitis, acute skin infection, adjustment disease, aneurysm and aortic atherosclerois among the conditions Dr. Kwok treats.
Internists near Dr. Kwok
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. Ester C. Kwok billed Medicare for 795 services in 2024
CMS data shows 795 Medicare services from Dr. Kwok across 9 procedure codes in 2024, for 307 Medicare patients. Medicare paid $99,308 for them. Every service was in an office.
Dr. Kwok's Medicare services by type, 2023 to 2024
- 2023
- 2024
- Office and hospital visits
- 2023: 7442024: 60019%
- Other services
- 2023: 2242024: 15630%
- Tests and treatments
- 2023: 982024: 3960%
Dr. Kwok compared with the California median for internists, 2024
- Dr. Kwok
- California median
- Medicare services
- 795vs 3612.2 times
- Medicare patients
- 307vs 1512.0 times
- Part D claims
- 2,550vs 4216.1 times
Medians across 15,815 internists in California with Dmand AI profiles that report each measure.
Dr. Kwok'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.
Need commercial claims for Dr. Kwok?
Medicare shows one payer. Book a meeting to get commercial claims data for Dr. Kwok and other internists in California.
Sources: Medicare Physician & Other Practitioners - by Provider and Service (CMS), 2024 data; and Dmand AI Peer Benchmarks
Dr. Ester C. Kwok treated 307 Medicare patients in 2024, average age 74
CMS counts 307 Medicare patients who saw Dr. Kwok in 2024. The largest group is 65 to 74, with 170 patients. 75% of them have high cholesterol, and 74% have high blood pressure. Their average risk score is 0.99, where 1.00 is the Medicare average.
Across all payers, Dmand AI patient panel data puts Dr. Kwok's median patient age at 64, with 68% women.
Dr. Kwok's Medicare patients by age, 2024
CMS leaves out age groups with fewer than 11 patients.
Dr. Kwok's Medicare patients by sex, 2024
- Women22373%
- Men8427%
Chronic conditions among Dr. Kwok's Medicare patients, 2024
- High cholesterol75%
- High blood pressure74%
- Arthritis36%
- Osteoporosis36%
- Diabetes23%
- Ischemic heart disease21%
- Chronic kidney disease19%
- Cancer16%
Share of Medicare patients with each condition. A patient can have several.
Dr. Kwok's patients across all payers
Dmand AI patient panel data covers Medicare, Medicaid and commercial patients.
Patient panel by age, all payers
Median age 64
Patient panel by sex, all payers
- Women68%
- Men30%
Sources: Dmand AI Patient Panel Data; and Medicare Physician & Other Practitioners - by Provider (CMS), 2024 data
Dr. Ester C. Kwok wrote 3,097 Medicare Part D claims in 2024
In 2024, Dr. Kwok wrote 3,097 Medicare Part D claims for 348 patients. 91% of them were for generic drugs. CMS names the drug for 2,550 of them, across 50 drugs with 11 or more claims each, at $147,918 in total drug cost. In 2023, CMS named 2,819 claims across 52 drugs.
Dr. Kwok's Part D claims by kind of drug, 2024
- Generic2,803 claims91%
- Brand-name and other294 claims9%
Dr. Kwok'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. Kwok's Part D claims, 2024
- Antibiotics4%131 of 3,097 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: 2,8192024: 2,55010%
Drugs named by CMS: 50 in 2024, 52 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. Ester C. Kwok offers telehealth to Medicare patients
Dr. Kwok accepts Medicare assignment, so Medicare's approved amount is taken as full payment. CMS lists Dr. Kwok as offering telehealth.
- Accepts Medicare assignment
- Yes
- Offers telehealth
- Yes
Source: Doctors and Clinicians National Downloadable File (CMS)
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Dr. Ester C. Kwok received $45 in industry payments in 2023
CMS Open Payments shows 2 general payments to Dr. Kwok from 1 drug or device company in 2023. Food and beverage make up the largest share, 100% of the total. Exact Sciences Corporation paid the most, $45.
Companies that paid Dr. Kwok the most, 2023 to 2023
Share is of all general payments to this clinician.
Source: Open Payments (CMS), 2025 data, released July 7, 2026
Dr. Ester C. Kwok graduated from McGovern Medical School
Dr. Kwok graduated from McGovern Medical School in 1989. Dr. Kwok is a member of ACP.
- Medical school
- Board certified in internal medicine
Source: Dmand AI Professional Profile Data
Dr. Ester C. Kwok accepts plans from 14 insurance carriers
Dr. Kwok is in network with 14 carriers, including Aetna, Blue Cross Blue Shield of Michigan and United Healthcare. PPO plans come from the most carriers, 9. Check the plan with the practice before a visit.
- Aetna
- Blue Cross Blue Shield of Michigan
- United Healthcare
- Elevance
- Blue Cross Blue Shield of Massachusetts
- HCSC
- Regence Health Plans
- Alliant Health Plans
- +6 more carriersWith a free account
Plan types Dr. Kwok accepts, by number of carriers
- PPO9
- Medicare7
- HMO5
- EPO4
- POS4
Source: Dmand AI Insurance Network Data
Sources for Dr. Ester C. Kwok'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 |
| Insurance carriers and plan types | Dmand AI Insurance Network 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. Ester C. Kwok
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. Ester C. Kwok's NPI number?
Dr. Ester C. Kwok's NPI number is 1790886034. It was assigned on September 26, 2006, and it is active in the NPI Registry.
What kind of doctor is Dr. Ester C. Kwok?
Dr. Ester C. Kwok is an internist in Stanford, California. The primary specialty in the NPI Registry is Internal Medicine Physician (taxonomy code 207R00000X).
Where does Dr. Ester C. Kwok practice?
Dr. Kwok practices at 300 Pasteur Drive, Stanford, CA 94305. Dr. Kwok's primary practice is Stanford Hospital at 300 Pasteur Drive in Stanford, California, part of Stanford University. Dmand AI also links Dr. Kwok to 2 hospitals, 1 physician office, 1 group practice or clinic and 1 home health agency.
What is Dr. Ester C. Kwok's office phone number?
The practice phone on file for Dr. Kwok is (650) 723-4000.
What is Dr. Ester C. Kwok's medical license number?
Dr. Kwok's California license number on file is A050957.
Which hospitals is Dr. Ester C. Kwok affiliated with?
Dr. Kwok practices at Stanford Hospital at 300 Pasteur Drive in Stanford, California. Dr. Kwok is also affiliated with El Camino Health - Mountain View Hospital. Dmand AI links Dr. Kwok to 2 more hospitals.
What medical group is Dr. Ester C. Kwok part of?
Dr. Kwok is linked to El Camino Health Medical Network.
Does Dr. Ester C. Kwok accept Medicare?
Yes. CMS data shows Dr. Kwok billed Medicare for 795 services in 2024, and Dr. Kwok accepts Medicare assignment.
Does Dr. Ester C. Kwok offer telehealth?
Yes. The CMS Doctors and Clinicians file lists Dr. Kwok as offering telehealth services.
How many Medicare patients does Dr. Ester C. Kwok see?
CMS counts 307 Medicare patients who saw Dr. Kwok in 2024, with an average age of 74.
Show 7 more questionsShow fewer questions
Is Dr. Ester C. Kwok board certified?
Yes. Dr. Kwok is board certified in internal medicine by the American Board of Internal Medicine.
What services does Dr. Ester C. Kwok bill to Medicare?
In 2024, Dr. Kwok's most billed Medicare services were office visit, established patient (99214), office visit, established patient (99215) and medicare service (G0439).
Where did Dr. Ester C. Kwok go to medical school?
Dr. Kwok graduated from McGovern Medical School in 1989.
What drugs does Dr. Ester C. Kwok prescribe most?
In 2024 Medicare Part D data, Dr. Kwok's most prescribed drugs by claims were Rosuvastatin Calcium, Losartan Potassium and Amlodipine Besylate.
Has Dr. Ester C. Kwok received payments from drug or device companies?
CMS Open Payments shows $45 in general payments to Dr. Kwok from 1 company from 2023 to 2023. The largest total came from Exact Sciences Corporation.
How long has Dr. Ester C. Kwok been practicing?
Dr. Kwok graduated from medical school in 1989, 37 years ago.
What insurance does Dr. Ester C. Kwok accept?
Dr. Kwok is in network with 14 carriers, including Aetna, Blue Cross Blue Shield of Michigan and United Healthcare. PPO plans come from the most carriers, 9. Check the plan with the practice before a visit.
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