Healthcare provider profile · identity verified

Mark T. Shimazaki, DO

Internal Medicine · SANTA CLARA, CA · NPI 1275611717

Profile state: partd only Open Payments: 2025 Medicare Part D: 2024 Last identity check: 2026-08-10 Page data build: 2026-08-12

Verified facts

What the public records show

We did not find matching Open Payments records for this doctor in 2025.

These records do not establish that a payment influenced prescribing or medical care.

Payment overview · 2025

General Payments

We did not find matching Open Payments records for this doctor in the selected program year.

Separate record types

Research & Ownership

Research Payments (direct recipient): not present in the loaded data

Associated Research Funding (for example, named PI): not present in the loaded data

Ownership / Investment: not present in the loaded data

These categories are never added into the General Payments headline. Associated research funding must not be described as money the doctor personally received unless the source record supports that conclusion.

Analysis 1 · Payment-linked products

Products named in Open Payments records

No payment-linked product analysis is available because no matching General Payment records were found for the selected year.

Public prescribing for products named in payments

There is no explicit payment-product set available for a Part D comparison.

The presence of the same drug in both datasets does not show that a payment caused or influenced a prescription.

Analysis 2 · Same-company prescribing overlap

Drugs reported in other payments from the same company that also appear in Medicare Part D

This analysis is independent from products named on this doctor’s individual payment records. A row appears only when the exact Open Payments reporting entity paid this doctor, that same reporting entity reported the drug or biological on at least 10 loaded General Payment records involving at least 2 distinct recipient NPIs, and this doctor has the same non-generic brand in public Part D data. This does not mean the company owns or manufactures the drug.

There is no payer-company set available for this comparison.

These facts do not show that a payment was for the drug, that the company owns or manufactures the drug, or that a payment caused or influenced prescribing.

Public Medicare Part D data

Provider-and-drug rows loaded for 2024

BrandGenericClaimsBeneficiaries
Atorvastatin CalciumAtorvastatin Calcium422147
Amlodipine BesylateAmlodipine Besylate26588
Losartan PotassiumLosartan Potassium19764
Levothyroxine SodiumLevothyroxine Sodium19253
Tamsulosin HclTamsulosin Hcl15263
LisinoprilLisinopril15050
SimvastatinSimvastatin11839
Alendronate SodiumAlendronate Sodium11135
Metformin HclMetformin Hcl10033
Metoprolol TartrateMetoprolol Tartrate9637
Trazodone HclTrazodone Hcl8226
Fluticasone PropionateFluticasone Propionate8026
Albuterol Sulfate HfaAlbuterol Sulfate7425
OzempicSemaglutide7412
HydrochlorothiazideHydrochlorothiazide7325
Hydralazine HclHydralazine Hcl6926
GabapentinGabapentin6828
Lisinopril-HydrochlorothiazideLisinopril/Hydrochlorothiazide6821
FurosemideFurosemide6423
AtenololAtenolol6218
Hydrocodone-AcetaminophenHydrocodone/Acetaminophen6214
Pantoprazole SodiumPantoprazole Sodium6224
OmeprazoleOmeprazole6123
Rosuvastatin CalciumRosuvastatin Calcium5820
JardianceEmpagliflozin5720
Losartan-HydrochlorothiazideLosartan/Hydrochlorothiazide5622
Metformin Hcl ErMetformin Hcl5520
Metoprolol SuccinateMetoprolol Succinate5217
FinasterideFinasteride5017
GlipizideGlipizide5019
LovastatinLovastatin4916
FamotidineFamotidine4820
PradaxaDabigatran Etexilate Mesylate4416
FluocinonideFluocinonide4218
Zolpidem TartrateZolpidem Tartrate38suppressed
AlvescoCiclesonide3714
Triamcinolone AcetonideTriamcinolone Acetonide3626
AllopurinolAllopurinol3514
Donepezil HclDonepezil Hcl3412
Spiriva RespimatTiotropium Bromide3311
Terazosin HclTerazosin Hcl3211
Tramadol HclTramadol Hcl3111
Pravastatin SodiumPravastatin Sodium28suppressed
Ipratropium BromideIpratropium Bromide2712
SpironolactoneSpironolactone27suppressed
FenofibrateFenofibrate26suppressed
MirtazapineMirtazapine2614
Sertraline HclSertraline Hcl26suppressed
Warfarin SodiumWarfarin Sodium26suppressed
Wixela InhubFluticasone Propion/Salmeterol26suppressed
ClopidogrelClopidogrel Bisulfate25suppressed
Duloxetine HclDuloxetine Hcl25suppressed
EliquisApixaban25suppressed
Adacel TdapDiph,pertuss(Acell),tet Vac/Pf2424
Tizanidine HclTizanidine Hcl24suppressed
ChlorthalidoneChlorthalidone23suppressed
Montelukast SodiumMontelukast Sodium23suppressed
Clobetasol PropionateClobetasol Propionate22suppressed
EszopicloneEszopiclone21suppressed
NaproxenNaproxen21suppressed
PrednisonePrednisone2018
Trospium ChlorideTrospium Chloride20suppressed
Fluoxetine HclFluoxetine Hcl19suppressed
Humulin NInsulin Nph Human Isophane19suppressed
Memantine HclMemantine Hcl19suppressed
Propranolol HclPropranolol Hcl19suppressed
Stiolto RespimatTiotropium Br/Olodaterol Hcl19suppressed
CarvedilolCarvedilol18suppressed
CefadroxilCefadroxil1816
ClonazepamClonazepam18suppressed
ClotrimazoleClotrimazole18suppressed
Acetaminophen-CodeineAcetaminophen With Codeine17suppressed
Potassium ChloridePotassium Chloride17suppressed
Veo Insulin SyringeSyrge-Ndl,ins 0.3 Ml Half Mark17suppressed
ColchicineColchicine16suppressed
LatanoprostLatanoprost16suppressed
HydrocortisoneHydrocortisone15suppressed
AcyclovirAcyclovir14suppressed
Azelastine HclAzelastine Hcl14suppressed
Isosorbide Mononitrate ErIsosorbide Mononitrate14suppressed
Oxycodone HclOxycodone Hcl14suppressed
TemazepamTemazepam14suppressed
FluorouracilFluorouracil1312
Humulin N KwikpenInsulin Nph Human Isophane13suppressed
Ibandronate SodiumIbandronate Sodium13suppressed
Potassium Citrate ErPotassium Citrate13suppressed
AzithromycinAzithromycin1212
Dorzolamide-TimololDorzolamide Hcl/Timolol Maleat12suppressed
Doxycycline MonohydrateDoxycycline Monohydrate12suppressed
Escitalopram OxalateEscitalopram Oxalate12suppressed
Ondansetron OdtOndansetron12suppressed
Ropinirole HclRopinirole Hcl12suppressed
AmoxicillinAmoxicillin11suppressed
Amoxicillin-Clavulanate PotassAmoxicillin/Potassium Clav11suppressed
Bupropion Hcl SrBupropion Hcl11suppressed
Clindamycin PhosphateClindamycin Phosphate11suppressed
Diltiazem 24hr Er (Cd)Diltiazem Hcl11suppressed
DuleraMometasone/Formoterol11suppressed
Glipizide ErGlipizide11suppressed
IbuprofenIbuprofen11suppressed
Ondansetron HclOndansetron Hcl11suppressed
Quetiapine FumarateQuetiapine Fumarate11suppressed

Timeline

Payment and prescribing data by year

Open Payments and Medicare Part D may refer to different years. They are shown separately rather than aligned as if they describe the same period.

YearGeneral PaymentsMain payerExplicit productsCompany overlapsPart D coverage
2025
2024 Complete

Questions to ask

Questions you could discuss with your doctor

These are general questions generated from reviewed templates. They are not personalized medical advice.

Sources and limitations

How to read this page

Loaded source releases

DatasetYearPublicationSource
CMS Open Payments — General Payments 2025 2026-06-30 Original source
Medicare Part D Prescribers by Provider and Drug 2024 2026-05-06 Original source
NPPES Data Dissemination V2 current / reference data 2026-08-10 Original source

Methodology version: 2.1

Editorial template version: 2.4

Product contract version: 2.0

Schema version: 0.7.0

Page data build: 2026-08-12T23:34:59.370714+00:00

Publication policy: eligible for indexing after public-launch controls are enabled

Full methodology · Questions & answers · Report a possible error