NPI registry status
Active
2026 NPPES data Internal Medicine Physician NPI 1881717197 M.D.
Verify on CMS → Michael Kwok, M.D.
Internal Medicine Physician in Diamond Bar, California.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 174,792 in Internal Medicine Physician, and covers specialty classification, practice address, and Medicare Part D prescribing data when reported. According to CMS, every field reflects the provider's official federal registration, see our methodology.
Federal data, no proprietary rating.
We show these CMS records as-is - no composite score, no star rating, no editorial opinion layered on top.
Prescribing volume
3K
Medicare Part D claims · 290 beneficiaries · Internal Medicine Physician avg: 3K
Generic prescribing
91%
generic claims · 8% brand-name · higher generic rates reduce patient out-of-pocket costs
Source: CMS Medicare Part D Prescriber Public Use File, 2024
What the federal data shows
Michael Kwok, M.D. filed 2,765 Medicare Part D claims in 2024 as an Internal Medicine Physician in Diamond Bar, California, prescribing 91% generic.
- 3K
- Part D claims, 2024
- 91%
- generic prescribing
- Likely
- board-certified (heuristic)
- ≥87th
- pct by Part D claim volume (lower-bound band)
Every figure on this page comes straight from federal CMS records (NPPES, Medicare Part D, MIPS, Open Payments) - no proprietary rating or editorial opinion is applied.
Federal trust snapshot
What official records show about Michael Kwok, M.D.
Federal records show an active NPI with Medicare Part D prescribing activity — verifiable registry data, not a proprietary rating.
- Verified
NPI registry status
Active listing in the CMS National Provider Identifier Registry (NPI 1881717197), first enumerated 04/10/2007.
Source: CMS NPPES
- Reported
Medicare Part D participation
Filed 2,765 Medicare Part D prescription claims in the 2023 CMS public use file — indicates active Medicare prescribing participation.
Source: CMS Part D Prescriber PUF
- Reported
Board certification signal
Heuristic suggests board-certified status based on ABMS-eligible specialty taxonomy plus active CMS participation signals — not a direct ABMS verification.
- Reported
Hospital affiliations
1 CMS Care Compare hospital affiliation on record — practice footprint from the Doctors and Clinicians file.
Source: CMS Care Compare
- State context
State board disciplinary context
California statewide board action statistics are published annually — these figures describe aggregate state activity, not Michael Kwok, M.D.'s individual license status. Verify directly with the state medical board.
Source: MBC annual report 2023
- Not in federal data
Individual sanction lookup
PlainDoctor does not publish per-provider disciplinary determinations. Confirm current license and any individual actions through the state medical board or FSMB verification service.
Source: State medical board / FSMB
This trust snapshot summarizes only what appears in federal CMS/NPPES public records. It is not a composite score, star rating, patient review, or clinical recommendation. PlainDoctor never fabricates reviews or AggregateRating schema.
Compare Kwok with other Internal Medicine Physician providers
Same primary specialty, same federal CMS NPPES roster.
All 10 Internal Medicine Physician providers in Diamond Bar, CA →
Also enrolled in California
- Dr. Jacob Aaron, MD San Francisco, CA
- Dr. Alistair Aaronson, MD Stanford, CA
- Dr. Jose Abad., MD Sacramento, CA
- Dr. Donna Abare, MD Oakland, CA
- Marce Abare Scotts Valley, CA
- Dr. Samuel Abarte, M.D. Chula Vista, CA
Other specialties in Diamond Bar: Speech-Language Pathologist (45) · Pharmacist (43) · General Practice Dentistry (39) · Acupuncturist (36)
CMS NPPES provider registry desk
NPI 1881717197 · Internal Medicine Physician
NPI-10 · ENUM-MID · TAX-MEGA · RX-MID · BOOK-MID · PHOTO-ENUM
- NPI-10 1881717197
- ENUM-MID 2007
- TAX-MEGA 175K Internal Medicine
- RX-MID 2,765
- BOOK-MID 20,403 in California
- PHOTO-ENUM Andrea Kondracke, M.D. · 2007
Michael Kwok, M.D.'s Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2024, across all CMS prescribers nationally
2,765 ≥ 87th percentile 87% of 1,416,883 prescribers are in lower value bands
Each bar is a band; taller bars hold more prescribers. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
The percentile is a conservative 100-claim band: it counts only prescribers in lower claim-volume bands. Medicare Part D claim volume is activity context, not a quality measure or recommendation. See methodology § corpus placement.
Source CMS Medicare Part D Prescriber Public Use File · 2024
✓
Board certification likely (heuristic, not verified)
Michael Kwok, M.D. practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 1 hospital affiliation - signals consistent with board-certified status. For verified board certification, see CertificationMatters.org (the official ABMS public lookup).
What does the federal data show about Michael Kwok, M.D.?
Quality data not reportedPrimary specialty
Internal Medicine Physician
Medicare Part D claims
2,765 1% vs specialty avg
Specialty distribution in California
How Internal Medicine Physician compares to other specialties among California providers
Board certification
Not published by CMS
CMS does not publish a per-provider board-certification field in NPPES. PlainDoctor does not have a reliable per-specialty certification rate to show for Internal Medicine Physician. Verify directly:
How MIPS and board certification work
The Merit-based Incentive Payment System (MIPS) scores providers 0–100 across four performance categories: Quality, Cost, Promoting Interoperability, and Improvement Activities, weighted under 42 CFR §414.1380. Reporting is voluntary for many small practices, so absence of a MIPS score is not a quality signal.
Board certification through an ABMS or AOA member board signals voluntary post-licensure examination plus continuous Maintenance of Certification cycles. Verify any individual provider's status through certificationmatters.org (ABMS) or osteopathic.org (AOA).
Practice Address
Provider Details
| NPI | 1881717197 |
|---|---|
| Specialty | Internal Medicine Physician |
| Credentials | M.D. |
| Gender | Male |
| NPI Issued | 04/10/2007 |
Hospital and facility affiliations
Facilities where Michael Kwok, M.D. bills Medicare from. Star ratings (1-5) are CMS Hospital Compare's "Hospital overall rating" - a composite of mortality, readmission, patient experience, safety, timely care, and efficient use of medical imaging measures. Source: CMS Care Compare.
Southern California Permanente Medical Group
Los Angeles, CA
Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).
License & disciplinary context - California MBC 2023 annual report
Aggregate state board data only, NOT a determination of any individual provider's status. The figures below describe statewide disciplinary activity across all ~150K California medical licensees in 2023 - they are NOT specific to Michael Kwok, M.D.. To verify Michael Kwok, M.D.'s current license status, search the MBC public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.
576
Total board actions, California 2023
Across 556 cases
3.84
Actions per 1,000 licensees
California statewide rate
probation
Most common action type
186 cases
MBC publishes annual disciplinary statistics as part of public-record reporting under each state's Administrative Procedure Act. See the full breakdown by action type and year on the California disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.
Brand vs generic prescribing mix · Generic-heavy
Michael Kwok, M.D. - brand share 8.0%
Internal Medicine Physician average
8% brand-name claims vs 91% generic, on 2,765 2024 Medicare Part D claims.
The federal Medicare Part D Generic Dispensing Rate national benchmark sits near 90% generic / 10% brand for primary-care prescribers, per CMS Office of the Actuary 2024 estimates. Higher brand share is common in specialty prescribing where generic equivalents are not available.
Medicare Part D Prescribing Data
CMS Medicare Part D prescriber-level data for calendar year 2024.
2,765
Total Claims
$124K
Total Drug Cost
290
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 7,397.233
- Total Day Supply
- 217,892
- Brand vs Generic
- 8% brand / 91% generic
- Brand Drug Cost
- $74K
- Generic Drug Cost
- $49K
- Opioid Claims
- 71 (2.6% rate)
- Antibiotic Claims
- 35
Patient Demographics
- Average Patient Age
- 74.8 years
- Avg HCC Risk Score
- 1.11
- Gender Split
- 46% female / 54% male
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2024. Based on Medicare Part D data only.
What Michael Kwok, M.D. prescribes most
Top Medicare Part D drugs by claim count, 2024
- Atorvastatin Calcium
Atorvastatin Calcium
251 claims
- Amlodipine Besylate
Amlodipine Besylate
157 claims
- Lisinopril
Lisinopril
135 claims
- Losartan Potassium
Losartan Potassium
119 claims
- Rosuvastatin Calcium
Rosuvastatin Calcium
104 claims
- Metformin Hcl
Metformin Hcl
103 claims
- Glipizide 83
Glipizide
83 claims
- Hydrochlorothiazide 79
Hydrochlorothiazide
79 claims
| Drug | Claims |
|---|---|
| Atorvastatin Calcium | 251 |
| Amlodipine Besylate | 157 |
| Lisinopril | 135 |
| Losartan Potassium | 119 |
| Rosuvastatin Calcium | 104 |
| Metformin Hcl | 103 |
| Glipizide | 83 |
| Hydrochlorothiazide | 79 |
| Terazosin Hcl | 73 |
| Metformin Hcl Er Metformin Hcl | 67 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Internal Medicine Physician Overview
How Michael Kwok, M.D. fits within the Internal Medicine Physician landscape nationally.
174,792
Internal Medicine Physician Providers in US
56
States with Internal Medicine Physician
2,785
Avg Claims per Provider
Michael Kwok, M.D.'s 2,765 claims are below the specialty average of 2,785.
Nationwide Internal Medicine Physician peers with similar MIPS or enrollment year
Two federal-record peer sets for Kwok, both outside California so the neighborhoods are not geographic containment.
Same NPPES enumeration year (2007)
Same-specialty clinicians who entered the NPI registry in the same calendar year, outside this state.
Nearby Internal Medicine Physician Providers in California
Other clinicians with the same primary specialty enrolled in California, drawn from the same CMS NPPES roster as Kwok.
One of 20,403 Internal Medicine Physician providers enrolled in California, 11 are shown on this page.
Dr. Alexander Abary
MD
Long Beach, CA
Dr. Luba Abascal
MD
San Francisco, CA
Dr. Michael Abate
MD
Sacramento, CA
Dr. Wali Abawi
D.O.
Joshua Tree, CA
Hazel Abaya
Thousand Oaks, CA
Compare Internal Medicine Physician nationally: see state-by-state distribution →
Frequently Asked Questions
What is Michael Kwok, M.D.'s specialty? ▼
Michael Kwok, M.D. specializes in Internal Medicine Physician and practices in Diamond Bar, California. Credentials: M.D..
How much does Michael Kwok, M.D. prescribe under Medicare Part D? ▼
In 2024, Michael Kwok, M.D. wrote 2,765 Medicare Part D claims totaling $124K in drug costs for 290 beneficiaries.
Where is Michael Kwok, M.D. located? ▼
Michael Kwok, M.D. is located at 3220 S BREA CANYON RD, Diamond Bar, CA, 91765. Phone: (909) 594-1848.
What is Michael Kwok, M.D.'s NPI number? ▼
Michael Kwok, M.D.'s National Provider Identifier (NPI) is 1881717197, issued on 04/10/2007.
Does Michael Kwok, M.D. prescribe more brand-name or generic drugs? ▼
Michael Kwok, M.D.'s prescribing is 8% brand-name and 91% generic drugs by claim count, with $74K in brand drug costs.
Does Michael Kwok, M.D. prescribe opioids? ▼
Yes, Michael Kwok, M.D. had 71 opioid claims in 2024 with an opioid prescribing rate of 2.6%.
How many Internal Medicine Physician providers are there in the US? ▼
There are 174,792 Internal Medicine Physician providers across 56 states in the US. The average Internal Medicine Physician provider writes 2,785 Medicare Part D claims per year.
What drugs does Michael Kwok, M.D. prescribe most often? ▼
Based on 2024 Medicare Part D data, Michael Kwok, M.D.'s most frequently prescribed drugs include Atorvastatin Calcium, Amlodipine Besylate, Lisinopril. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Michael Kwok, M.D. accept Medicare? ▼
Michael Kwok, M.D. appears in CMS Medicare data with 2,765 Part D claims and 290 Medicare beneficiaries in 2024. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Michael Kwok, M.D.'s credentials? ▼
Michael Kwok, M.D.'s NPI is 1881717197 with credentials M.D.. You can verify this through the NPPES NPI Registry, check state medical board records, and confirm board certification through the ABMS or AOA.
Data Sources
View source datasets and methodology notes
- Provider Directory
- CMS National Plan and Provider Enumeration System (NPPES), download.cms.gov/nppes, updated monthly. Contains NPI, specialty, credentials, and practice location.
- Specialty Classification
- NUCC Health Care Provider Taxonomy (nucc.org), the industry standard for classifying provider specialties in Medicare and Medicaid billing.
- Prescribing Data
- CMS Medicare Part D Prescriber Public Use File (2024). Includes claims, drug costs, beneficiaries, and opioid prescribing rates.
- Limitations
- Provider data is self-reported to CMS. Prescribing data reflects Medicare Part D only and does not include commercial insurance, Medicaid, or cash prescriptions. Claims below 11 beneficiaries are suppressed by CMS for privacy.
See our complete data methodology for details on how we collect and process government data.
Data as of August 2026 (NPPES) / 2024 (Medicare Part D). Source: Centers for Medicare & Medicaid Services (CMS).
Disclaimer: Data from CMS NPPES and Medicare Part D. PlainDoctor does not rate or rank providers. Provider information is self-reported and may not be current. Always verify information directly with the provider. About · Methodology
Every figure on PlainDoctor is rendered directly from the federal CMS NPPES registry, Medicare Part D, MIPS, and Open Payments records, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of August 2026.