Sam S. Ahn, M.D.
Allergy & Immunology (Internal Medicine) Physician · Napa, CA
Sam S. Ahn, M.D. is an allergy & immunology (internal medicine) physician with a practice address in Napa, California, and NPI 1558423814, issued on Dec 14, 2006. Check the license (California 147289, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Sam S. Ahn
- Credential
- M.D.
- Primary taxonomy
- Allergy & Immunology (Internal Medicine) Physician 207RA0201X
- License number
- 147289 CA
Self-reported in NPPES; status is on the state search - Practice location
- 1100 Pear Tree LN, Napa, CA 94558
- Phone
- (707) 258-8100
- Enumerated
- Dec 14, 2006
- Record last updated
- Mar 7, 2023
- Fax
- (707) 258-0734
- Medicare enrollment
- Enrolled (PECOS I20170725004314); accepts Medicare assignment
- Medical or professional school
- Harvard Medical School, 2003
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest allergy & immunology (internal medicine) physician records → All 81 in California → Look up another NPI →
Also registered at 1100 Pear Tree LN
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Ravdeep Kaur, M.D.Allergy & Immunology (Internal Medicine) Physician1134567092
- Amber Keenan, FNPNurse Practitioner1972022465
- Kathleen Tajiri, MDAllergy & Immunology Physician1689624983
Verify Sam S. Ahn in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license 147289Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
2.8 times the Medicare Part D claims of the average allergy & immunology (internal medicine) physician in 2024
2,246 Medicare Part D claims for 427 beneficiaries, against an average of 789 among the 429 providers of this specialty who prescribed in Part D.
Most prescribed
- Ipratropium Bromide256 claims
- Montelukast Sodium204 claims
- Azelastine Hcl163 claims
- Albuterol Sulfate Hfa155 claims
- Trelegy Ellipta120 claims
- Levocetirizine Dihydrochloride113 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): 82.3 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).
Industry payments in 2024: $3,423.62
78 payments; by number, the most common kind was food and beverage; the largest payer was Genzyme Corporation. The 321 providers of this specialty with any payment received $7,456.30 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.
Bills Medicare through one group practice
- North Bay Allergy And AsthmaNapa, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Sam S. Ahn among 81 allergy & immunology (internal medicine) physician records in California
Sam S. Ahn, M.D. is one of 81 allergy & immunology (internal medicine) physician records with a practice address in California. 67% 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, 68% newer
- In a Medicare fileYes · 67% of these records are
- In the CMS Doctors and Clinicians fileYes · 57% of these records are
- Graduated2003 · median 2010 among the 46 with a school on file
- Record last updated2023 · 49% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RA0201X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Allergy & Immunology (Internal Medicine) Physician providers in California
There are 81 allergy & immunology (internal medicine) physician records in California.
All 81 in California → Every provider in Napa → Allergy & Immunology (Internal Medicine) Physician nationwide →
The 8 allergy & immunology (internal medicine) physician records with the nearest ZIP codes
- Ravdeep Kaur, M.D.Napa, CA 945581134567092
- Geoffrey Carlson, MDTravis Afb, CA 945351174865588
- Sally Bailey, MDSan Ramon, CA 945831700815677
- Imran Junaid, M.D.Concord, CA 945201285801787
- Linda Engelstad, MDOakland, CA 946021710997374
- Cynthia Ramirez, RNOakland, CA 946021134723174
- Andrew Engler, MDSan Mateo, CA 944011366400384
- Zahida Maskatia, M.D.San Mateo, CA 944011134364250
Common questions
What is Sam S. Ahn, M.D.'s NPI number?
Sam S. Ahn, M.D.'s National Provider Identifier (NPI) is 1558423814, issued on Dec 14, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Sam S. Ahn, M.D. located?
The NPPES record lists a practice address at 1100 Pear Tree LN, Napa, CA, 94558. Phone: (707) 258-8100. Providers update this record themselves, so call before visiting.
How can I verify Sam S. Ahn, M.D.'s license?
NPPES lists California license number 147289, 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 Sam S. Ahn, M.D. prescribe under Medicare Part D?
In 2024, Sam S. Ahn, M.D. had 2,246 Medicare Part D claims for 427 beneficiaries; the average among allergy & immunology (internal medicine) physician prescribers was 789. Part D covers Medicare prescriptions only.
What is Sam S. Ahn, M.D.'s MIPS final score?
The 2023 MIPS final score is 82.3 of 100. The average among 454,083 clinicians with a measured score was 83.5.
Source: CMS National Plan and Provider Enumeration System (NPPES), 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.