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Michael S Ahn, MD

Gastroenterology · Santa Clara

NPI 1225115173

Medicare standing
Clear
Enrolled, allowed to bill and order, not excluded
Plans that list them
4
1 carrier
Offices
2

Offices

2 locations · Permanente Medical Group Inc · 10,928 clinicians in this group

Looking this up.

Plans that list them

4 plans · 1 carrier

A missing listing does not mean out of network. Directories change, and a listing does not cover every office. Call Dr. Ahn’s office at (408) 851-1000 to confirm they take your plan. Ask about the office you use, its medical group, referrals and appointments.

Plans whose provider directory lists this clinician
Kaiser Permanente Dual Complete North P2 (HMO D-SNP)Kaiser PermanenteListedSep 1, 2026
Kaiser Permanente Dual Complete North P23 (HMO D-SNP)Kaiser PermanenteListedSep 1, 2026
Kaiser Permanente Sr Adv Basic Santa Clara (HMO)Kaiser PermanenteListedSep 1, 2026
Kaiser Permanente Sr Adv Enhanced Santa Clara (HMO)Kaiser PermanenteListedSep 1, 2026

California Medical Board record

Licence G80248 · Current

Licensed to practise in California · since 1994 · expires 2028-02-29 · University of Chicago, Pritzker School of Medicine.

No disciplinary actions, convictions, malpractice judgments or citations in this record.

Original Medicare doctor bills

This is what Medicare paid the clinician — not Medicare Advantage, and not the pharmacy.

Procedures Medicare counted

Procedure volume Medicare published
Colonoscopy1-10None
Upper gastrointestinal (GI) endoscopy for acid reflux1-10None

Drugs they prescribed that Part D paid

$362,563

Pharmacies billed $362,563 in 2024.

This is pharmacy cost, not the office bill, and not what patients paid.

413 generic and 92 brand-name prescriptions · $362,563 in drug cost · 17 antibiotic prescriptions.

Part D prescriptions only. The opioid rate is opioid prescriptions as a share of all this clinician's Part D prescriptions; surgeons and pain specialists run higher than others, so it is shown against the same specialty.

Largest Part D drug costs
Mesalamine77$40,988$532
Amjevita(Cf)13$23,946$1,842
Linzess18$12,038$669
Lubiprostone29$3,156$109
Gavilyte-C102$2,304$23
See all 10 drugs
Every Part D drug this clinician prescribed
Mesalamine77$40,988$532
Amjevita(Cf)13$23,946$1,842
Linzess18$12,038$669
Lubiprostone29$3,156$109
Gavilyte-C102$2,304$23
Budesonide Dr12$1,502$125
Omeprazole65$827$13
Pantoprazole33$517$16
Azathioprine13$403$31
Famotidine19$237$12

Year by year

Part D prescribing by year
2024505241None18%$362,563
20236284140% (0)20%$352,858
20224592530% (0)30%$276,922
20214182070% (0)27%$134,926
20204352390% (0)34%$184,743
20195103240% (0)23%$231,610
20185233280% (0)45%$289,407
20175533350% (0)20%$247,456
2016474254None25%$220,552
20154802990% (0)22%$126,833
2014415224None25%$118,264
20135923622% (13)9%$101,735

Part D prescriptions only. A drug prescribed to fewer than 11 people in a year is hidden.

See the drugs prescribed each year

2023: 9 drugs

Part D drugs prescribed in 2023
Lialda41$25,053$611
Mesalamine21$7,111$339
Gavilyte-C303$6,286$21
Sulfasalazine14$1,336$95
Omeprazole38$462$12
Famotidine27$386$14
Azathioprine11$326$30
Peg-3350 and Electrolytes11$278$25
Pantoprazole13$236$18

2022: 9 drugs

Part D drugs prescribed in 2022
Lialda45$27,916$620
Linzess11$6,872$625
Lubiprostone12$4,528$377
Gavilyte-C117$2,116$18
Sulfasalazine20$1,747$87
Famotidine39$537$14
Omeprazole40$460$12
Peg-3350 and Electrolytes17$347$20
Pantoprazole21$335$16

2021: 9 drugs

Part D drugs prescribed in 2021
Lialda51$29,284$574
Mesalamine29$11,559$399
Sulfasalazine26$1,719$66
Gavilyte-C63$958$15
Peg-3350 and Electrolytes43$872$20
Azathioprine11$599$54
Diphenoxylate-Atropine12$579$48
Omeprazole23$416$18
Famotidine26$415$16

2020: 11 drugs

Part D drugs prescribed in 2020
Humira13$107,732$8,287
Mesalamine45$14,537$323
Lialda21$12,034$573
Amitiza11$7,810$710
Gavilyte-C97$1,873$19
Sulfasalazine20$1,845$92
Pantoprazole17$998$59
Peg-3350 and Electrolytes29$621$21
Omeprazole15$407$27
Famotidine29$378$13
Peg 3350-Electrolyte11$297$27

2019: 12 drugs

Part D drugs prescribed in 2019
Humira13$105,043$8,080
Lialda29$31,020$1,070
Gavilyte-C231$8,299$36
Amitiza12$6,385$532
Linzess11$5,731$521
Mesalamine12$4,854$405
Ursodiol16$3,739$234
Budesonide Ec12$1,820$152
Sulfasalazine12$1,818$152
Omeprazole22$611$28
Gavilyte-G11$266$24
Famotidine15$178$12

2018: 9 drugs

Part D drugs prescribed in 2018
Humira13$101,634$7,818
Lialda42$65,773$1,566
Gavilyte-C131$4,773$36
Ursodiol16$3,755$235
Peg 3350-Electrolyte99$3,584$36
Sulfasalazine19$3,355$177
Lamivudine Hbv11$1,969$179
Omeprazole41$1,361$33
Dicyclomine11$279$25

2017: 12 drugs

Part D drugs prescribed in 2017
Humira13$96,052$7,389
Lialda41$74,103$1,807
Ursodiol23$10,434$454
Sulfasalazine14$4,224$302
Gavilyte-C245$4,165$17
Lamivudine Hbv18$3,160$176
Omeprazole40$1,539$38
Cholestyramine11$1,041$95
Pantoprazole16$990$62
Dicyclomine14$440$31
Famotidine15$343$23
Amitriptyline12$160$13

2016: 9 drugs

Part D drugs prescribed in 2016
Humira12$72,292$6,024
Lialda44$70,834$1,610
Ursodiol26$15,622$601
Sulfasalazine11$3,229$294
Gavilyte-C168$2,856$17
Omeprazole43$2,233$52
Cholestyramine11$740$67
Dicyclomine11$623$57
Famotidine17$378$22

2015: 7 drugs

Part D drugs prescribed in 2015
Lialda38$68,590$1,805
Ursodiol31$12,557$405
Sulfasalazine11$3,522$320
Gavilyte-C204$3,484$17
Omeprazole48$2,956$62
Azathioprine11$596$54
Famotidine19$537$28

2014: 8 drugs

Part D drugs prescribed in 2014
Lialda38$56,954$1,499
Ursodiol31$15,006$484
Omeprazole41$2,478$60
Gavilyte-C86$1,478$17
Azathioprine15$707$47
Dicyclomine11$643$58
Peg 3350-Electrolyte36$612$17
Famotidine29$532$18

2013: 9 drugs

Part D drugs prescribed in 2013
Lialda13$19,041$1,465
Gavilyte-C253$4,324$17
Ursodiol30$4,050$135
Omeprazole50$3,127$63
Diphenoxylate-Atropine12$1,092$91
Azathioprine15$830$55
Famotidine34$653$19
Dicyclomine16$478$30
Ondansetron11$263$24

Money from drug and device companies

$43 in 2024

Industry payments by year
202411None$43
202211None$77

Paid work is consulting, speaking, honoraria and royalties, as opposed to meals and travel.

A payment is not proof that care is biased.

Payments by company
Boston ScientificExalt Model D$43
1 payment
  • Meals for Exalt Model D · 2024-02-23 · $43
See the published payment
Every published payment
Boston ScientificMeals · 2024-02-23Exalt Model D$43
See earlier years (2022)

2022: $77

Payments by company in 2022
Boston ScientificExalt Model D$77
1 payment
  • Meals for Exalt Model D · 2022-09-21 · $77

Professional record

NPI
1225115173
Licence
CA G80248California G80248: Current · expires 2028-02-29
Trained
University of Chicago, Pritzker School of Medicine, 1993
Gender
Male
More record details
Sole proprietor
No
Medicaid ID
CA 00G802480
Taxonomy
Federal specialty code 207RG0100X (207RG0100X)
Mailing address
1800 Harrison St Fl 7, Oakland, CA, 94612
NPI first listed
2006-10-31
NPI last updated
2021-12-06

This is when the NPI record was last certified, not a medical board exam.

This office lists an electronic records connection.