Ann Joo Lee, M.D.
Gastroenterology Physician · Downey, CA
Ann Joo Lee, M.D. is a gastroenterology physician with a practice address in Downey, California, and NPI 1396979126, issued on May 7, 2009. Check the license (California 136160, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Ann Joo Lee
- Credential
- M.D.
- Primary taxonomy
- Gastroenterology Physician 207RG0100X
- License numbers
- 136160 CA
036-167184 IL
Self-reported in NPPES; status is on the state search - Practice location
- 10441 Lakewood Blvd Ste B, Downey, CA 90241
- Phone
- (562) 869-4497
- Enumerated
- May 7, 2009
- Record last updated
- Dec 29, 2025
- Medicare enrollment
- Enrolled (PECOS I20150817002129); accepts Medicare assignment
- Entity
- Type 1 · individual
8 nearest gastroenterology physician records → All 2,140 in California → Look up another NPI →
Also registered at 10441 Lakewood Blvd Ste B
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Niani Conerly, DNP, APRN, FNP-BCNurse Practitioner1649742206
Verify Ann Joo Lee in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license 136160Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
69% fewer Medicare Part D claims than the average gastroenterology physician in 2024
253 Medicare Part D claims for 150 beneficiaries, against an average of 811 among the 16,445 providers of this specialty who prescribed in Part D. Brand-name drugs were 11% of claims.
Most prescribed
- Gavilyte-G49 claims
- Pantoprazole Sodium37 claims
- Sod Sulf-Potass Sulf-Mag Sulf35 claims
- Omeprazole34 claims
- Famotidine27 claims
- Peg-3350 And Electrolytes18 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 practice group's MIPS final score for 2023 (Medicare payment program): 81.5 of 100
The Merit-based Incentive Payment System score is reported for the practice group, not for one clinician alone. 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, group reporting; category weights for 2023 (qpp.cms.gov).
Bills Medicare through 2 group practices
- Advocate Health And Hospitals CorporationChicago, IL
- Healthcare Partners Affiliates Medical GroupCarson, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Ann Joo Lee among 2,140 gastroenterology physician records in California
Ann Joo Lee, M.D. is one of 2,140 gastroenterology physician records with a practice address in California. 83% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2009, is newer than 69% of them.
- NPI issued2009 · 69% of these records are older, 28% newer
- In a Medicare fileYes · 83% of these records are
- In the CMS Doctors and Clinicians fileYes · 72% of these records are
- Graduated2008 · median 2002 among the 1,538 with a school on file
- Record last updated2025 · 60% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RG0100X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Gastroenterology Physician providers in California
There are 2,140 gastroenterology physician records in California.
All 2,140 in California → Every provider in Downey → Gastroenterology Physician nationwide →
The 8 gastroenterology physician records with the nearest ZIP codes
- Gaurang Chaurushia, MDDowney, CA 902411538126131
- Kevin Dholaria, M.D.Downey, CA 902411629343736
- Andrew Nguyen, MDDowney, CA 902411154784783
- Sushil Ojha, MDDowney, CA 902411053377093
- Rajeev Attam, MDDowney, CA 902421184694309
- Terence Chiu, MDDowney, CA 902421427083229
- Gareth Dulai, MDDowney, CA 902421164457883
- Paul Frenkiel, M.D.Downey, CA 902401245284645
Common questions
What is Ann Joo Lee, M.D.'s NPI number?
Ann Joo Lee, M.D.'s National Provider Identifier (NPI) is 1396979126, issued on May 7, 2009. An NPI identifies a provider in billing; it is not a license.
Where is Ann Joo Lee, M.D. located?
The NPPES record lists a practice address at 10441 Lakewood Blvd Ste B, Downey, CA, 90241. Phone: (562) 869-4497. Providers update this record themselves, so call before visiting.
How can I verify Ann Joo Lee, M.D.'s license?
NPPES lists California license number 136160, 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 Ann Joo Lee, M.D. prescribe under Medicare Part D?
In 2024, Ann Joo Lee, M.D. had 253 Medicare Part D claims for 150 beneficiaries; the average among gastroenterology physician prescribers was 811. Part D covers Medicare prescriptions only.
What is Ann Joo Lee, M.D.'s MIPS final score?
The 2023 MIPS final score is 81.5 of 100, reported for the practice group. 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.