Dale Ritzo, M.D.
Internal Medicine Physician · San Mateo, CA
Dale Ritzo, M.D. is an internal medicine physician with a practice address in San Mateo, California, and NPI 1255499323, issued on Dec 4, 2006. Check the license (California G50169, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Dale Ritzo
- Credential
- M.D.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- G50169 CA
Self-reported in NPPES; status is on the state search - Practice location
- 101 S San Mateo Dr, San Mateo, CA 94401
- Phone
- (650) 343-4003
- Enumerated
- Dec 4, 2006
- Entity
- Type 1 · individual
Also registered at 101 S San Mateo Dr
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Marieta Angtuaco, M.D.Specialist1548324536
- Jack Bernstein, MDInternal Medicine Physician1457301384
- Catrina Blake, FNPNurse Practitioner1205472115
- Jonathan Briskin, M.D.Cardiovascular Disease Physician1417032376
- Doris Burton, MDDiagnostic Radiology Physician1285837906
- Mary Dobbins, M.D.Internal Medicine Physician1407837693
Verify Dale Ritzo in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license G50169Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS, AOA, NCCPA, AANPNot checked
29% more Medicare Part D claims than the average internal medicine physician in 2024
3,598 Medicare Part D claims for 286 beneficiaries, against an average of 2,785 among the 127,794 providers of this specialty who prescribed in Part D. Brand-name drugs were 11% of claims. 45 claims were for opioids.
Most prescribed
- Levothyroxine Sodium261 claims
- Rosuvastatin Calcium231 claims
- Amlodipine Besylate213 claims
- Atorvastatin Calcium205 claims
- Lorazepam163 claims
- Zolpidem Tartrate104 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 Medicare quality score for 2023: 6.3 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).
45 internal medicine physician records list a San Mateo practice address
They are 45 of the 3,909 NPPES records with a San Mateo practice address, and 20,403 internal medicine physician records in California.
All 45 in San Mateo → All 20,403 in California → Every provider in San Mateo →
Other internal medicine physician records in California
- Jacob Aaron, MDSan Francisco, CA1407202518
- Alistair Aaronson, MDStanford, CA1457628760
- Jose Abad., MDSacramento, CA1144607219
- Donna Abare, MDOakland, CA1386722155
- Marce AbareScotts Valley, CA1457744708
- Samuel Abarte, M.D.Chula Vista, CA1578535498
- Alexander Abary, MDLong Beach, CA1104995919
- Luba Abascal, MDSan Francisco, CA1023180874
- Michael Abate, MDSacramento, CA1548248131
- Wali Abawi, D.O.Joshua Tree, CA1104362268
Common questions
What is Dale Ritzo, M.D.'s NPI number?
Dale Ritzo, M.D.'s National Provider Identifier (NPI) is 1255499323, issued on Dec 4, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Dale Ritzo, M.D. located?
The NPPES record lists a practice address at 101 S San Mateo Dr, San Mateo, CA, 94401. Phone: (650) 343-4003. Providers update this record themselves, so call before visiting.
How can I verify Dale Ritzo, M.D.'s license?
NPPES lists California license number G50169, as entered by the provider. 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 Dale Ritzo, M.D. prescribe under Medicare Part D?
In 2024, Dale Ritzo, M.D. had 3,598 Medicare Part D claims for 286 beneficiaries; the average among internal medicine physician prescribers was 2,785. Part D covers Medicare prescriptions only.
What is Dale Ritzo, M.D.'s Medicare quality score?
The 2023 MIPS final score is 6.3 of 100. The average among 454,083 clinicians with a measured score was 83.5.
Source: CMS National Plan and Provider Enumeration System (NPPES), loaded Aug 27, 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.
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 Aug 27, 2026.