Healthcare provider profile · identity verified

David J Ringdahl, MD

Family Practice · MIDDLETON, WI · NPI 1154381457

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 Calcium474146
Amlodipine BesylateAmlodipine Besylate386111
LisinoprilLisinopril32089
Levothyroxine SodiumLevothyroxine Sodium23561
OmeprazoleOmeprazole18960
Rosuvastatin CalciumRosuvastatin Calcium18861
EliquisApixaban16232
HydrochlorothiazideHydrochlorothiazide14847
GabapentinGabapentin14742
FurosemideFurosemide14641
SimvastatinSimvastatin14638
Metoprolol SuccinateMetoprolol Succinate14435
Sertraline HclSertraline Hcl13434
Metformin Hcl ErMetformin Hcl13137
Losartan PotassiumLosartan Potassium12741
Tamsulosin HclTamsulosin Hcl12435
Metoprolol TartrateMetoprolol Tartrate10536
CarvedilolCarvedilol10232
Pantoprazole SodiumPantoprazole Sodium10022
Potassium ChloridePotassium Chloride9328
Trazodone HclTrazodone Hcl8923
AtenololAtenolol8323
Hydrocodone-AcetaminophenHydrocodone/Acetaminophen7421
Metformin HclMetformin Hcl6921
Oxycodone HclOxycodone Hcl6916
Pravastatin SodiumPravastatin Sodium6317
Albuterol Sulfate HfaAlbuterol Sulfate5321
PregabalinPregabalin5312
PrednisonePrednisone5215
ClonazepamClonazepam5113
ClopidogrelClopidogrel Bisulfate4912
Fluticasone PropionateFluticasone Propionate4919
Tizanidine HclTizanidine Hcl4815
Triamterene-HydrochlorothiazidTriamterene/Hydrochlorothiazid4613
Citalopram HbrCitalopram Hydrobromide43suppressed
Donepezil HclDonepezil Hcl43suppressed
EzetimibeEzetimibe43suppressed
Fluoxetine HclFluoxetine Hcl43suppressed
CelecoxibCelecoxib4211
AlprazolamAlprazolam41suppressed
Doxazosin MesylateDoxazosin Mesylate4112
GlimepirideGlimepiride4116
SpironolactoneSpironolactone4012
Ropinirole HclRopinirole Hcl39suppressed
Zolpidem TartrateZolpidem Tartrate38suppressed
BaclofenBaclofen37suppressed
FamotidineFamotidine37suppressed
Quetiapine FumarateQuetiapine Fumarate36suppressed
Solifenacin SuccinateSolifenacin Succinate35suppressed
Duloxetine HclDuloxetine Hcl3412
FarxigaDapagliflozin Propanediol34suppressed
Oxybutynin ChlorideOxybutynin Chloride34suppressed
MirtazapineMirtazapine33suppressed
Advair HfaFluticasone Propion/Salmeterol32suppressed
Warfarin SodiumWarfarin Sodium32suppressed
ChlorthalidoneChlorthalidone31suppressed
Triamcinolone AcetonideTriamcinolone Acetonide3118
Venlafaxine Hcl ErVenlafaxine Hcl31suppressed
Cyclobenzaprine HclCyclobenzaprine Hcl29suppressed
Diclofenac SodiumDiclofenac Sodium26suppressed
RisperidoneRisperidone26suppressed
TrulicityDulaglutide26suppressed
AllopurinolAllopurinol24suppressed
JardianceEmpagliflozin24suppressed
ValsartanValsartan24suppressed
Lisinopril-HydrochlorothiazideLisinopril/Hydrochlorothiazide23suppressed
Montelukast SodiumMontelukast Sodium23suppressed
SynthroidLevothyroxine Sodium23suppressed
IrbesartanIrbesartan22suppressed
Lantus SolostarInsulin Glargine,hum.Rec.Anlog22suppressed
MeloxicamMeloxicam22suppressed
NitrofurantoinNitrofurantoin Macrocrystal21suppressed
Wixela InhubFluticasone Propion/Salmeterol21suppressed
AmoxicillinAmoxicillin2014
CephalexinCephalexin20suppressed
Escitalopram OxalateEscitalopram Oxalate20suppressed
LorazepamLorazepam20suppressed
Fluticasone Propionate HfaFluticasone Propionate19suppressed
FenofibrateFenofibrate18suppressed
Hydroxyzine HclHydroxyzine Hcl18suppressed
JanuviaSitagliptin Phosphate18suppressed
Amoxicillin-Clavulanate PotassAmoxicillin/Potassium Clav1716
Diltiazem 24hr Er (Cd)Diltiazem Hcl17suppressed
FentanylFentanyl17suppressed
GemfibrozilGemfibrozil17suppressed
Oxybutynin Chloride ErOxybutynin Chloride17suppressed
Dicyclomine HclDicyclomine Hcl16suppressed
LansoprazoleLansoprazole16suppressed
LevetiracetamLevetiracetam16suppressed
OzempicSemaglutide16suppressed
DutasterideDutasteride15suppressed
Nitrofurantoin Mono-MacroNitrofurantoin Monohyd/M-Cryst1511
Bupropion Hcl SrBupropion Hcl14suppressed
Doxycycline HyclateDoxycycline Hyclate14suppressed
Ondansetron HclOndansetron Hcl14suppressed
Repatha SureclickEvolocumab14suppressed
Butalbital-Acetaminophen-CaffeButalb/Acetaminophen/Caffeine13suppressed
Ciprofloxacin HclCiprofloxacin Hcl13suppressed
FinasterideFinasteride13suppressed
Vitamin D2Ergocalciferol (Vitamin D2)13suppressed
XareltoRivaroxaban13suppressed
Benazepril-HydrochlorothiazideBenazepril/Hydrochlorothiazide12suppressed
LamotrigineLamotrigine12suppressed
Losartan-HydrochlorothiazideLosartan/Hydrochlorothiazide12suppressed
Paroxetine HclParoxetine Hcl12suppressed
Propranolol HclPropranolol Hcl12suppressed
Ultra-Fine Mini Pen NeedlePen Needle, Diabetic12suppressed
Benazepril HclBenazepril Hcl11suppressed
CilostazolCilostazol11suppressed
Pioglitazone HclPioglitazone Hcl11suppressed
Tramadol HclTramadol 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