Ari Katz, M.D.
Internal Medicine Physician · Walnut Creek, CA
Ari Katz, M.D. is an internal medicine physician with a practice address in Walnut Creek, California, and NPI 1902290828, issued on Mar 28, 2015. Check the license on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Ari Katz
- Credential
- M.D.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- 036146174 IL
Self-reported in NPPES; status is on the state search - Practice location
- 1535 Treat Blvd, Walnut Creek, CA 94598
- Phone
- (925) 296-9228
- Enumerated
- Mar 28, 2015
- Record last updated
- Dec 8, 2025
- Fax
- (925) 296-9227
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 17,696 in California → Look up another NPI →
Also registered at 1535 Treat Blvd
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Waheeda Hiller, MDInternal Medicine Physician1689642233
- Barry Rotman, MDInternal Medicine Physician1528083599
Verify Ari Katz in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of CaliforniaCheck the board
- 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
40% fewer Medicare Part D claims than the average internal medicine physician in 2024
1,908 Medicare Part D claims for 166 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D.
Most prescribed
- Atorvastatin Calcium156 claims
- Amlodipine Besylate98 claims
- Rosuvastatin Calcium89 claims
- Levothyroxine Sodium50 claims
- Losartan Potassium45 claims
- Metoprolol Succinate45 claims
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
The MIPS final score for 2023 (Medicare payment program): 94.1 of 100
The Merit-based Incentive Payment System score is reported for this clinician. Four categories are weighted into the final score; the average among 454,083 clinicians with a measured score was 83.5.
Source: CMS Quality Payment Program, MIPS performance year 2023; category weights for 2023 (qpp.cms.gov).
Industry payments in 2024: $382.41
8 payments; by number, the most common kind was food and beverage; the largest payer was Edwards Lifesciences Corporation. The 50,334 providers of this specialty with any payment received $1,303.06 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
Ari Katz among 17,696 internal medicine physician records in California
Ari Katz, M.D. is one of 17,696 internal medicine physician records with a practice address in California. 79% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2015, is newer than 76% of them.
- NPI issued2015 · 76% of these records are older, 21% newer
- In a Medicare fileYes · 79% of these records are
- In the CMS Doctors and Clinicians fileNo · 63% of these records are
- Record last updated2025 · 61% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207R00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
183 internal medicine physician records list a practice address in Walnut Creek
They are 183 of the 6,170 NPPES records with a practice address in Walnut Creek, and 17,696 internal medicine physician records in California.
All 17,696 in California → Every provider in Walnut Creek → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Anthony Bernens, MDWalnut Creek, CA 945981215983440
- Martin Braker, M.D.Walnut Creek, CA 945981922050095
- Mei Chow-Kwan, MDWalnut Creek, CA 945981689619330
- Lisa Craig, MDWalnut Creek, CA 945981699853754
- Jaya Francis, MDWalnut Creek, CA 945981962580548
- Tarannum Guller, MDWalnut Creek, CA 945981972532083
- Noushin Haddad-Tehrani, MDWalnut Creek, CA 945981215988878
- Waheeda Hiller, MDWalnut Creek, CA 945981689642233
Common questions
What is Ari Katz, M.D.'s NPI number?
Ari Katz, M.D.'s National Provider Identifier (NPI) is 1902290828, issued on Mar 28, 2015. An NPI identifies a provider in billing; it is not a license.
Where is Ari Katz, M.D. located?
The NPPES record lists a practice address at 1535 Treat Blvd, Walnut Creek, CA, 94598. Phone: (925) 296-9228. Providers update this record themselves, so call before visiting.
How can I verify Ari Katz, M.D.'s license?
Search the Medical Board of California at https://www.mbc.ca.gov/License-Verification/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Ari Katz, M.D. prescribe under Medicare Part D?
In 2024, Ari Katz, M.D. had 1,908 Medicare Part D claims for 166 beneficiaries; the average among internal medicine physician prescribers was 3,176. Part D covers Medicare prescriptions only.
What is Ari Katz, M.D.'s MIPS final score?
The 2023 MIPS final score is 94.1 of 100. The average among 454,083 clinicians with a measured score was 83.5.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.