Healthcare provider profile · identity verified

Robert J Ishak, M.D.

Internal Medicine · CHARLESTON, SC · NPI 1295727790

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 Calcium467156
Rosuvastatin CalciumRosuvastatin Calcium430136
Amlodipine BesylateAmlodipine Besylate30495
Losartan PotassiumLosartan Potassium22875
Levothyroxine SodiumLevothyroxine Sodium18557
LisinoprilLisinopril15449
OzempicSemaglutide14530
Duloxetine HclDuloxetine Hcl13939
Metoprolol SuccinateMetoprolol Succinate13646
OmeprazoleOmeprazole12147
Pantoprazole SodiumPantoprazole Sodium11349
HydrochlorothiazideHydrochlorothiazide10134
Tamsulosin HclTamsulosin Hcl9832
Trazodone HclTrazodone Hcl9831
EzetimibeEzetimibe9736
Sertraline HclSertraline Hcl9126
Metformin HclMetformin Hcl9032
GabapentinGabapentin8838
AllopurinolAllopurinol8024
EliquisApixaban7726
FurosemideFurosemide7731
Olmesartan MedoxomilOlmesartan Medoxomil7723
Losartan-HydrochlorothiazideLosartan/Hydrochlorothiazide6621
Metformin Hcl ErMetformin Hcl6520
Montelukast SodiumMontelukast Sodium6120
MounjaroTirzepatide5911
FamotidineFamotidine5628
FarxigaDapagliflozin Propanediol5614
SpironolactoneSpironolactone5518
Pravastatin SodiumPravastatin Sodium5216
Albuterol Sulfate HfaAlbuterol Sulfate5032
Zolpidem TartrateZolpidem Tartrate5014
CarvedilolCarvedilol4815
PregabalinPregabalin4414
LevetiracetamLevetiracetam42suppressed
Lisinopril-HydrochlorothiazideLisinopril/Hydrochlorothiazide4211
Metoprolol TartrateMetoprolol Tartrate4215
Fluticasone PropionateFluticasone Propionate4117
JardianceEmpagliflozin3914
LorazepamLorazepam3715
Tramadol HclTramadol Hcl3717
Bupropion XlBupropion Hcl3512
Potassium ChloridePotassium Chloride3512
Fluoxetine HclFluoxetine Hcl3314
CelecoxibCelecoxib3211
MirtazapineMirtazapine31suppressed
ClonazepamClonazepam30suppressed
AzithromycinAzithromycin2924
Escitalopram OxalateEscitalopram Oxalate2912
Hydroxyzine HclHydroxyzine Hcl2912
FinasterideFinasteride28suppressed
MeloxicamMeloxicam27suppressed
Alendronate SodiumAlendronate Sodium26suppressed
TrulicityDulaglutide2611
ClopidogrelClopidogrel Bisulfate25suppressed
Amoxicillin-Clavulanate PotassAmoxicillin/Potassium Clav2424
Donepezil HclDonepezil Hcl24suppressed
AlprazolamAlprazolam23suppressed
Warfarin SodiumWarfarin Sodium2312
Venlafaxine Hcl ErVenlafaxine Hcl21suppressed
Esomeprazole MagnesiumEsomeprazole Magnesium20suppressed
AtenololAtenolol19suppressed
BaclofenBaclofen18suppressed
ValsartanValsartan18suppressed
Zolpidem Tartrate ErZolpidem Tartrate18suppressed
Azelastine HclAzelastine Hcl16suppressed
Clonidine HclClonidine Hcl16suppressed
IrbesartanIrbesartan16suppressed
Triamterene-HydrochlorothiazidTriamterene/Hydrochlorothiazid16suppressed
AmoxicillinAmoxicillin15suppressed
Breztri AerosphereBudesonide/Glycopyr/Formoterol15suppressed
GlimepirideGlimepiride15suppressed
LansoprazoleLansoprazole15suppressed
Lantus SolostarInsulin Glargine,hum.Rec.Anlog15suppressed
NaproxenNaproxen15suppressed
SynthroidLevothyroxine Sodium15suppressed
Amlodipine Besylate-BenazeprilAmlodipine Besylate/Benazepril14suppressed
Benazepril HclBenazepril Hcl14suppressed
EntrestoSacubitril/Valsartan14suppressed
Ezetimibe-SimvastatinEzetimibe/Simvastatin14suppressed
FenofibrateFenofibrate14suppressed
Nitrofurantoin Mono-MacroNitrofurantoin Monohyd/M-Cryst14suppressed
Olmesartan-HydrochlorothiazideOlmesartan/Hydrochlorothiazide14suppressed
Spironolactone-HctzSpironolact/Hydrochlorothiazid14suppressed
Sulfamethoxazole-TrimethoprimSulfamethoxazole/Trimethoprim1414
XareltoRivaroxaban14suppressed
Citalopram HbrCitalopram Hydrobromide13suppressed
EstradiolEstradiol13suppressed
Folic AcidFolic Acid13suppressed
Hydralazine HclHydralazine Hcl13suppressed
Ipratropium BromideIpratropium Bromide13suppressed
SimvastatinSimvastatin13suppressed
Klor-Con M20Potassium Chloride12suppressed
LovastatinLovastatin12suppressed
MisoprostolMisoprostol12suppressed
Amitriptyline HclAmitriptyline Hcl11suppressed
DiazepamDiazepam11suppressed
Diltiazem 24hr Er (Cd)Diltiazem Hcl11suppressed
Isosorbide Mononitrate ErIsosorbide Mononitrate11suppressed
Levocetirizine DihydrochlorideLevocetirizine Dihydrochloride11suppressed
MethylprednisoloneMethylprednisolone1111
Ondansetron HclOndansetron Hcl11suppressed
RamiprilRamipril11suppressed
Ropinirole HclRopinirole 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
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