Dr. Michael S. Ahn, MD
- Part D claims, 2024
- 505
- Publications
- 1
- Hospital affiliations
- 1
- Industry payments
- $618
- Medical group
- 1
- Practice address
- 710 Lawrence Expy, Santa Clara, CA 95051
- Practice phone
- Call (408) 851-1000
- Professional email
- Get professional email
- Personal email
- Get personal email
- Mobile number
- Get mobile number
Primary practice
Permanente Medical Group Inc
Santa Clara, California
Find Dr. Ahn's professional email, personal email and mobile number
Dmand AI checks each channel through healthcare-specific waterfall enrichment. See what is on file with a free account, with practice phones, licenses and affiliations.
Dr. Michael S. Ahn is a gastroenterologist in Santa Clara, California
Dr. Ahn practices at Permanente Medical Group Inc in Santa Clara, California.
Dr. Ahn's NPI, 1225115173, was assigned on October 31, 2006. Dr. Ahn graduated from Pritzker School of Medicine in 1993. Dr. Ahn holds California license G80248.
- NPI
- 1225115173NPI Registry (opens in a new tab)
- Medicare PAC ID
- 7315128865
- NPI enumeration date
- October 31, 2006
- NPI status
- Active
- Accepts Medicare assignment
- Yes
- Practice phone
- (408) 851-1000
- Professional email
- Get email
- Personal email
- Get email
- Mobile number
- Get number
- Sex
- Male
- Estimated age
- 59
- Medical school graduation
- 1993
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; Dmand AI Practice Data; and Doctors and Clinicians National Downloadable File (CMS)
Dr. Michael S. Ahn practices at Permanente Medical Group Inc in Santa Clara, California
Dr. Ahn's primary practice is Permanente Medical Group Inc, at 710 Lawrence Expy, Santa Clara, CA 95051 in Santa Clara County. The practice phone is (408) 851-1000.
- Permanente Medical Group Inc710 Lawrence Expy, Santa Clara, CA 95051 · Santa Clara CountyPhone(408) 851-1000
Sources: NPPES NPI Registry (CMS); and Dmand AI Practice Data
Dr. Michael S. Ahn is affiliated with 3 sites of care and 1 medical group
Dr. Ahn's primary practice is Permanente Medical Group Inc in Santa Clara, California. Dr. Ahn is also affiliated with Santa Clara Medical Center. The medical group on file is The Permanente Medical Group, Inc. Dmand AI also links Dr. Ahn to 1 more group practice or clinic, named with a free account.
Sources: NPPES NPI Registry (CMS); Dmand AI Practice Data; and Dmand AI Affiliation Data
Dmand AI tracks the EHR system at Dr. Michael S. Ahn's practice
Dmand AI tracks the electronic health record (EHR) system at each site where Dr. Ahn practices, 2 sites in all. Vendor and product names are available with a free account.
| Site | EHR vendor and product |
|---|---|
| Permanente Medical Group Inc | Available with a free account |
| +2 more affiliated sites | Available with a free account |
Source: Dmand AI Technology Install Data
For health IT teams
Dmand AI maps EHR vendors, IT decision makers and buying committees across each health system and 6.2K+ hospitals, with verified contacts in the same login.
Dr. Michael S. Ahn is one of 1,977 gastroenterologists in California
Gastroenterology is Dr. Ahn's primary specialty in the NPI Registry, under taxonomy code 207RG0100X. Dr. Ahn is board certified in gastroenterology by the American Board of Internal Medicine. Dr. Ahn is licensed in California.
Specialties and state licenses
- Gastroenterology, CaliforniaPrimary
Gastroenterologists near Dr. Ahn
Counts of gastroenterologists with a Dmand AI profile, by place and practice. Each opens the list.
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; and Dmand AI Peer Benchmarks
Dr. Michael S. Ahn's patients have a median age of 63
Across all payers, Dmand AI patient panel data puts Dr. Ahn's median patient age at 63, with 58% women.
Dr. Ahn's patients across all payers
Dmand AI patient panel data covers Medicare, Medicaid and commercial patients.
Patient panel by age, all payers
Median age 63
Patient panel by sex, all payers
- Women58%
- Men42%
Source: Dmand AI Patient Panel Data
Dr. Michael S. Ahn wrote 505 Medicare Part D claims in 2024
In 2024, Dr. Ahn wrote 505 Medicare Part D claims for 241 patients. 82% of them were for generic drugs. CMS names the drug for 381 of them, across 10 drugs with 11 or more claims each, at $85,919 in total drug cost. In 2023, CMS named 479 claims across 9 drugs.
Dr. Ahn's Part D claims by kind of drug, 2024
- Generic413 claims82%
- Brand-name92 claims18%
Dr. Ahn's most prescribed drugs by claims, 2024
CMS names a drug when it has 11 or more claims. Share is of the claims for drugs CMS names.
Drug classes CMS tracks in Dr. Ahn's Part D claims, 2024
- Antibiotics3%17 of 505 claims
Share of all Part D claims for each drug class CMS reports on. Classes with no claims are left out.
Part D claims for drugs CMS names, 2023 to 2024
- 2023
- 2024
- Claims for drugs CMS names
- 2023: 4792024: 38120%
Drugs named by CMS: 10 in 2024, 9 in 2023.
Sources: Medicare Part D Prescribers - by Provider and Drug (CMS), 2024 data, released May 6, 2026; and Medicare Part D Prescribers - by Provider (CMS), 2024 data
How Dr. Michael S. Ahn takes part in Medicare
Dr. Ahn accepts Medicare assignment, so Medicare's approved amount is taken as full payment.
- Accepts Medicare assignment
- Yes
Colonoscopy: 1 to 10 procedures (CMS shows small counts as a range)
Upper gastrointestinal (GI) endoscopy for acid reflux: 1 to 10 procedures (CMS shows small counts as a range)
Sources: Doctors and Clinicians National Downloadable File (CMS); and Doctors and Clinicians Utilization Data (CMS)
For MedTech and pharma teams
Filter 7.4M+ HCPs by Medicare procedures, Part D drugs and Open Payments history, then reach them with verified contacts in one login.
Dr. Michael S. Ahn has 1 publication on record
Dmand AI links 1 paper to Dr. Ahn.
Recent publications by Dr. Ahn
See who Dr. Ahn researches with
Physician Network Discovery turns co-authorship, shared hospitals and shared groups into a map of who Dr. Ahn works with, so you can find a warm path to the right gastroenterologists.
Sources: PubMed (National Library of Medicine); and Dmand AI Research Linkage
Dr. Michael S. Ahn received $618 in industry payments from 2018 to 2024
CMS Open Payments shows 3 general payments to Dr. Ahn from 1 drug or device company from 2018 to 2024. Travel and lodging make up the largest share, 81% of the total. Boston Scientific Corporation paid the most, $618.
General payments to Dr. Ahn by program year, 2018 to 2024
General payments to Dr. Ahn by kind, 2018 to 2024
- Travel and lodging$49781%
- Food and beverage$12019%
Companies that paid Dr. Ahn the most, 2018 to 2024
Share is of all general payments to this clinician.
Source: Open Payments (CMS), 2025 data, released July 7, 2026
Dr. Michael S. Ahn has 2 awards and honors on record
Dmand AI lists 2 awards for Dr. Ahn, most recently CMS Stage 1 2012 in 2011.
Awards and honors for Dr. Ahn
- 2011
- CMS Stage 1 2012
- Undated
- Checkbook Top Doc
Source: Dmand AI Professional Profile Data
Dr. Michael S. Ahn graduated from Pritzker School of Medicine
Dr. Ahn graduated from Pritzker School of Medicine in 1993.
- Medical school
- Board certified in gastroenterology
Source: Dmand AI Professional Profile Data
Dr. Michael S. Ahn accepts plans from 2 insurance carriers
Dr. Ahn is in network with 2 carriers, including Kaiser Permanente and CMS Medicare. EPO plans come from the most carriers, 1. Check the plan with the practice before a visit.
- Kaiser Permanente
- CMS Medicare
Plan types Dr. Ahn accepts, by number of carriers
- EPO1
- HMO1
- Medicare1
- POS1
Source: Dmand AI Insurance Network Data
Sources for Dr. Michael S. Ahn's profile data
| Data on this page | Source |
|---|---|
| NPI, name, sex, specialty and licenses | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Professional Profile Data |
| Practice locations and phone | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Practice Data |
| Primary practice, affiliations and health system | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Practice DataDmand AI Affiliation Data |
| Medicare patients and the all-payer patient panel | Dmand AI Patient Panel Data |
| Part D prescribing | Medicare Part D Prescribers - by Provider and Drug (CMS) (opens in a new tab)Medicare Part D Prescribers - by Provider (CMS) (opens in a new tab) |
| MIPS scores, telehealth, assignment and procedure percentiles | Doctors and Clinicians National Downloadable File (CMS) (opens in a new tab)Doctors and Clinicians Utilization Data (CMS) (opens in a new tab) |
| Publications, topics and co-authors | PubMed (National Library of Medicine) (opens in a new tab)Dmand AI Research Linkage |
| Industry payments | Open Payments (CMS) (opens in a new tab) |
| Awards and committee roles | Dmand AI Professional Profile Data |
| Training, board certification and memberships | Dmand AI Professional Profile Data |
| Insurance carriers and plan types | Dmand AI Insurance Network Data |
| EHR at each practice site | Dmand AI Technology Install Data |
| Similar physicians | Dmand AI Affiliation Data |
Data last refreshed October 2026Report an inaccuracyRemove my information
FAQ
Frequently asked questions about Dr. Michael S. Ahn
Spotted something out of date? Email hello@dmand.ai and we will check the record. Contact details live in the free trial.
What is Dr. Michael S. Ahn's NPI number?
Dr. Michael S. Ahn's NPI number is 1225115173. It was assigned on October 31, 2006, and it is active in the NPI Registry.
What kind of doctor is Dr. Michael S. Ahn?
Dr. Michael S. Ahn is a gastroenterologist in Santa Clara, California. The primary specialty in the NPI Registry is Gastroenterology Physician (taxonomy code 207RG0100X).
Where does Dr. Michael S. Ahn practice?
Dr. Ahn practices at 710 Lawrence Expy, Santa Clara, CA 95051. Dr. Ahn's primary practice is Permanente Medical Group Inc in Santa Clara, California. Dmand AI also links Dr. Ahn to 1 group practice or clinic.
What is Dr. Michael S. Ahn's office phone number?
The practice phone on file for Dr. Ahn is (408) 851-1000.
What is Dr. Michael S. Ahn's medical license number?
Dr. Ahn holds California license G80248.
Which hospitals is Dr. Michael S. Ahn affiliated with?
Dr. Ahn is affiliated with Santa Clara Medical Center.
What medical group is Dr. Michael S. Ahn part of?
Dr. Ahn is linked to The Permanente Medical Group, Inc.
Does Dr. Michael S. Ahn accept Medicare?
Yes. CMS lists Dr. Ahn as accepting Medicare assignment.
Is Dr. Michael S. Ahn board certified?
Yes. Dr. Ahn is board certified in gastroenterology by the American Board of Internal Medicine.
Where did Dr. Michael S. Ahn go to medical school?
Dr. Ahn graduated from Pritzker School of Medicine in 1993.
Show 5 more questionsShow fewer questions
What drugs does Dr. Michael S. Ahn prescribe most?
In 2024 Medicare Part D data, Dr. Ahn's most prescribed drugs by claims were Gavilyte-C, Mesalamine and Omeprazole.
Has Dr. Michael S. Ahn received payments from drug or device companies?
CMS Open Payments shows $618 in general payments to Dr. Ahn from 1 company from 2018 to 2024. The largest total came from Boston Scientific Corporation.
How long has Dr. Michael S. Ahn been practicing?
Dr. Ahn graduated from medical school in 1993, 33 years ago.
Does Dr. Michael S. Ahn do research?
Dmand AI links 1 publication to Dr. Ahn.
What insurance does Dr. Michael S. Ahn accept?
Dr. Ahn is in network with 2 carriers, including Kaiser Permanente and CMS Medicare. EPO plans come from the most carriers, 1. Check the plan with the practice before a visit.
Selling to gastroenterology practices?
See gastroenterologists in California by site of care and group
Find the practices, groups and hospitals they work with, and the right people to contact at each.
- 30 days free
- Self-serve
- No credit card