Healthcare provider profile · identity verified

Warren David Johnston, MD

Allopathic & Osteopathic Physicians|Internal Medicine|Cardiovascular Disease · ORANGE, CA · NPI 1427052802

Profile state: payments and partd 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

CMS Open Payments records show Warren David Johnston, MD received $112.48 in general payments during 2025 across 6 reported records.

Amgen Inc. accounted for 67.2% of that reported general-payment amount.

The Open Payments records used for this analysis explicitly named 3 associated products.

A separate comparison found the same explicitly named product in public Medicare Part D data: Eliquis.

E.R. Squibb & Sons, L.L.C. reported payments to this doctor in 2025. Across the 2025 Open Payments General Payment records loaded for this analysis, that same reporting entity reported ELIQUIS as an associated drug or biological on 27956 records involving 14870 distinct recipient NPIs. Public Medicare Part D data also shows 359 claims for Eliquis by this doctor in 2024.

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

Payment overview · 2025

General Payments

$112.48

6 reported records · 2 companies

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.

Who paid this doctor?

Companies in 2025 General Payments

Reported companyCanonical companyAmountShareRecordsYear
Amgen Inc. Unresolved — no canonical attribution shown $75.5467.2%42025
E.R. Squibb & Sons, L.L.C. Unresolved — no canonical attribution shown $36.9432.8%22025

What were the payments for?

Payment categories

CategoryAmountRecords
Food and Beverage$112.486

A meal, consulting fee, royalty, and travel payment describe different kinds of reported relationships and should not be interpreted as equivalent.

Analysis 1 · Payment-linked products

Products named in Open Payments records

Reported productTypeReported companyRelated amount*RecordsYear
REPATHA
Normalized: repatha
Biological Amgen Inc. $75.54 4 2025
Source payment records
ELIQUIS
Normalized: eliquis
Drug E.R. Squibb & Sons, L.L.C. $20.55 1 2025
Source payment records
CAMZYOS
Normalized: camzyos
Drug E.R. Squibb & Sons, L.L.C. $16.39 1 2025
Source payment records

* Product-associated amounts are non-additive because one payment record may name more than one product.

These products were named on specific Open Payments records. A named product does not show that the payment influenced treatment or prescribing.

Public prescribing for products named in payments

Open Payments productPayment yearPart D brandPart D yearClaimsMatch methodSource
ELIQUIS
eliquis
2025 Eliquis 2024 359 exact normalized Medicare Part D

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.

Paying companyPayment yearDrug reported by same entityOpen Payments evidencePart DClaimsBeneficiaries
E.R. Squibb & Sons, L.L.C.
Exact reporting entity; no affiliate inference
2025 ELIQUIS
open payments reported associated product
CMS Open Payments — General Payments
27956 supporting records · 14870 recipient NPIs · example record 1184377713
Eliquis · 2024
Exact normalized brand match · 1 Part D row
359 118

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
Rosuvastatin CalciumRosuvastatin Calcium1105387
Metoprolol SuccinateMetoprolol Succinate551184
Amlodipine BesylateAmlodipine Besylate436137
EliquisApixaban359118
Atorvastatin CalciumAtorvastatin Calcium328107
Losartan PotassiumLosartan Potassium31197
CarvedilolCarvedilol26783
Metoprolol TartrateMetoprolol Tartrate17353
Repatha SureclickEvolocumab16647
EzetimibeEzetimibe12545
FurosemideFurosemide11643
LisinoprilLisinopril9132
ClopidogrelClopidogrel Bisulfate9027
ChlorthalidoneChlorthalidone8732
EntrestoSacubitril/Valsartan7121
Potassium ChloridePotassium Chloride7122
NitroglycerinNitroglycerin5841
Diltiazem 24hr Er (Cd)Diltiazem Hcl5318
XareltoRivaroxaban5015
FarxigaDapagliflozin Propanediol4917
AtenololAtenolol4814
SimvastatinSimvastatin4415
FenofibrateFenofibrate4015
Warfarin SodiumWarfarin Sodium40suppressed
HydrochlorothiazideHydrochlorothiazide38suppressed
Benazepril HclBenazepril Hcl36suppressed
SpironolactoneSpironolactone3611
Clonidine HclClonidine Hcl3416
ValsartanValsartan34suppressed
Hydralazine HclHydralazine Hcl3214
Diltiazem 24hr ErDiltiazem Hcl2911
Praluent PenAlirocumab29suppressed
Flecainide AcetateFlecainide Acetate27suppressed
Pantoprazole SodiumPantoprazole Sodium23suppressed
SotalolSotalol Hcl22suppressed
Diltiazem 24hr Er (Xr)Diltiazem Hcl20suppressed
Ranolazine ErRanolazine19suppressed
Isosorbide Mononitrate ErIsosorbide Mononitrate17suppressed
Repatha SyringeEvolocumab16suppressed
VascepaIcosapent Ethyl15suppressed
PradaxaDabigatran Etexilate Mesylate14suppressed
Klor-Con 10Potassium Chloride12suppressed
Pravastatin SodiumPravastatin Sodium12suppressed
ClonidineClonidine11suppressed
DigoxinDigoxin11suppressed
Dilt-XrDiltiazem Hcl11suppressed
Enalapril MaleateEnalapril Maleate11suppressed
Nitroglycerin PatchNitroglycerin11suppressed
Verapamil ErVerapamil Hcl11suppressed

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 $112.48 · 6 records Amgen Inc. CAMZYOS, ELIQUIS, REPATHA 1
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