Joseph Manuel Alonzo, M.D.
Internal Medicine Physician · Covina, CA
Joseph Manuel Alonzo, M.D. is an internal medicine physician with a practice address in Covina, California, and NPI 1225077050, issued on Jun 6, 2006. Check the license (California A45798, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Joseph Manuel Alonzo
- Credential
- M.D.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- A45798 CA
Self-reported in NPPES; status is on the state search - Practice location
- 420 W Rowland St, Covina, CA 91723
- Phone
- (626) 331-6411
- Enumerated
- Jun 6, 2006
- Record last updated
- Dec 3, 2025
- Fax
- (626) 251-1559
- Medicare enrollment
- Enrolled (PECOS I20090725000117); accepts Medicare assignment
- Medical or professional school
- University Of California, Geffen School Of Medicine, 1984
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 17,696 in California → Look up another NPI →
Also registered at 420 W Rowland St
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Mary Absood, M.D.Internal Medicine Physician1497735906
- Nancy Aceves, RN, FNPFamily Nurse Practitioner1235171703
- Sarah Anh, M.D.Emergency Medicine Physician1104037159
- Travis Boyer, FNPFamily Nurse Practitioner1265901870
- Annamari Cabrera, MDPediatrics Physician1881653434
- Gail Campofiore, MDFamily Medicine Physician1447262258
Verify Joseph Manuel Alonzo in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A45798Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
3.8 times the Medicare Part D claims of the average internal medicine physician in 2024
11,934 Medicare Part D claims for 940 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 11% of claims. 116 claims were for opioids.
Most prescribed
- Atorvastatin Calcium958 claims
- Losartan Potassium543 claims
- Amlodipine Besylate542 claims
- Metformin Hcl493 claims
- Levothyroxine Sodium375 claims
- Lisinopril370 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.
Bills Medicare through one group practice
- Healthcare Partners Affiliates Medical GroupCovina, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Joseph Manuel Alonzo among 17,696 internal medicine physician records in California
Joseph Manuel Alonzo, 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 2006, is newer than 5% of them.
- NPI issued2006 · 5% of these records are older, 56% newer
- In a Medicare fileYes · 79% of these records are
- In the CMS Doctors and Clinicians fileYes · 63% of these records are
- Graduated1984 · median 2004 among the 11,065 with a school on file
- 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).
35 internal medicine physician records list a practice address in Covina
They are 35 of the 3,736 NPPES records with a practice address in Covina, and 17,696 internal medicine physician records in California.
All 17,696 in California → Every provider in Covina → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Mary Absood, M.D.Covina, CA 917231497735906
- Harry Chao, MDCovina, CA 917231487613451
- Kamini Chari, M.D.Covina, CA 917231265489280
- Jerry Cimmarusti, MDCovina, CA 917231386603322
- Vahid Javaherian, DOCovina, CA 917231609836972
- Ahmereen Khan, M.D.Covina, CA 917231174562243
- Sanjay Khedia, M.D.Covina, CA 917231326063801
- Arlene Nepomuceno, MDCovina, CA 917231043279037
Common questions
What is Joseph Manuel Alonzo, M.D.'s NPI number?
Joseph Manuel Alonzo, M.D.'s National Provider Identifier (NPI) is 1225077050, issued on Jun 6, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Joseph Manuel Alonzo, M.D. located?
The NPPES record lists a practice address at 420 W Rowland St, Covina, CA, 91723. Phone: (626) 331-6411. Providers update this record themselves, so call before visiting.
How can I verify Joseph Manuel Alonzo, M.D.'s license?
NPPES lists California license number A45798, 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 Joseph Manuel Alonzo, M.D. prescribe under Medicare Part D?
In 2024, Joseph Manuel Alonzo, M.D. had 11,934 Medicare Part D claims for 940 beneficiaries; the average among internal medicine physician prescribers was 3,176. Part D covers Medicare prescriptions only.
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.