Healthcare provider profile · identity verified

Dena Witthaus, D.O.

Internal Medicine · PORTLAND, OR · NPI 1528354966

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 Calcium333103
LisinoprilLisinopril25487
Hydrocodone-AcetaminophenHydrocodone/Acetaminophen24870
Oxycodone HclOxycodone Hcl22769
Losartan PotassiumLosartan Potassium22578
Levothyroxine SodiumLevothyroxine Sodium21965
Amlodipine BesylateAmlodipine Besylate21274
Albuterol Sulfate HfaAlbuterol Sulfate19966
Rosuvastatin CalciumRosuvastatin Calcium18057
SimvastatinSimvastatin15347
GabapentinGabapentin13551
Trazodone HclTrazodone Hcl10734
Metoprolol TartrateMetoprolol Tartrate10439
Metformin HclMetformin Hcl10132
OmeprazoleOmeprazole9634
AtenololAtenolol9233
Ondansetron OdtOndansetron8829
Pantoprazole SodiumPantoprazole Sodium8437
PradaxaDabigatran Etexilate Mesylate8029
FurosemideFurosemide7937
Oxycodone-AcetaminophenOxycodone Hcl/Acetaminophen7914
Alendronate SodiumAlendronate Sodium7731
Duloxetine HclDuloxetine Hcl7724
Potassium ChloridePotassium Chloride7530
GlipizideGlipizide7326
Metoprolol SuccinateMetoprolol Succinate7325
Tamsulosin HclTamsulosin Hcl7133
Metformin Hcl ErMetformin Hcl7029
Sertraline HclSertraline Hcl6920
Losartan-HydrochlorothiazideLosartan/Hydrochlorothiazide6722
LorazepamLorazepam6435
Humulin NInsulin Nph Human Isophane6324
CephalexinCephalexin6157
Citalopram HbrCitalopram Hydrobromide5920
AlvescoCiclesonide5417
MethocarbamolMethocarbamol5412
Lisinopril-HydrochlorothiazideLisinopril/Hydrochlorothiazide5220
Nitrofurantoin Mono-MacroNitrofurantoin Monohyd/M-Cryst5251
HydrochlorothiazideHydrochlorothiazide4818
IbuprofenIbuprofen4816
CarvedilolCarvedilol4717
AllopurinolAllopurinol4616
Spiriva RespimatTiotropium Bromide4617
MirtazapineMirtazapine4412
Montelukast SodiumMontelukast Sodium4413
JardianceEmpagliflozin4115
PrednisonePrednisone4131
Tramadol HclTramadol Hcl4014
Fluticasone PropionateFluticasone Propionate3916
ValacyclovirValacyclovir Hcl3819
Wixela InhubFluticasone Propion/Salmeterol3816
SpironolactoneSpironolactone3716
Pravastatin SodiumPravastatin Sodium3613
TorsemideTorsemide36suppressed
Fluoxetine HclFluoxetine Hcl35suppressed
PregabalinPregabalin3513
Triamcinolone AcetonideTriamcinolone Acetonide3522
Warfarin SodiumWarfarin Sodium3511
Bupropion XlBupropion Hcl3212
EstradiolEstradiol3222
ClopidogrelClopidogrel Bisulfate30suppressed
Donepezil HclDonepezil Hcl3011
Doxycycline MonohydrateDoxycycline Monohydrate3027
Humulin RInsulin Regular, Human3012
MeloxicamMeloxicam3018
Buspirone HclBuspirone Hcl29suppressed
Hydroxyzine HclHydroxyzine Hcl28suppressed
Propranolol HclPropranolol Hcl28suppressed
Doxepin HclDoxepin Hcl27suppressed
HydrocortisoneHydrocortisone2717
NystatinNystatin27suppressed
ClonazepamClonazepam26suppressed
Morphine Sulfate ErMorphine Sulfate26suppressed
Veo Insulin SyringeSyringe-Needle,insulin,0.5 Ml2412
Tizanidine HclTizanidine Hcl23suppressed
Veo Insulin SyringeSyringe And Needle,insulin,1ml23suppressed
FamotidineFamotidine22suppressed
OzempicSemaglutide22suppressed
Diltiazem 24hr Er (Cd)Diltiazem Hcl21suppressed
Escitalopram OxalateEscitalopram Oxalate2011
BaclofenBaclofen19suppressed
AmoxicillinAmoxicillin1813
Pramipexole DihydrochloridePramipexole Di-Hcl18suppressed
Sumatriptan SuccinateSumatriptan Succinate18suppressed
Triamterene-HydrochlorothiazidTriamterene/Hydrochlorothiazid18suppressed
Venlafaxine Hcl ErVenlafaxine Hcl18suppressed
Morphine SulfateMorphine Sulfate17suppressed
Isosorbide Mononitrate ErIsosorbide Mononitrate16suppressed
CefuroximeCefuroxime Axetil1514
Nortriptyline HclNortriptyline Hcl15suppressed
Ropinirole HclRopinirole Hcl15suppressed
Terazosin HclTerazosin Hcl15suppressed
Ipratropium BromideIpratropium Bromide14suppressed
Memantine HclMemantine Hcl14suppressed
Sulfamethoxazole-TrimethoprimSulfamethoxazole/Trimethoprim1414
Amoxicillin-Clavulanate PotassAmoxicillin/Potassium Clav1312
Dextroamphetamine-AmphetamineDextroamphetamine/Amphetamine13suppressed
EliquisApixaban13suppressed
FentanylFentanyl13suppressed
FinasterideFinasteride13suppressed
FluconazoleFluconazole1313
FluoridexFluoride (Sodium)13suppressed
ShingrixVaricella-Zoster Ge/As01b/Pf1312
TemazepamTemazepam13suppressed
ChlorthalidoneChlorthalidone12suppressed
Ciprofloxacin HclCiprofloxacin Hcl1212
DiazepamDiazepam12suppressed
Hydromorphone HclHydromorphone Hcl12suppressed
Lidocaine Hcl ViscousLidocaine Hcl12suppressed
Trospium ChlorideTrospium Chloride12suppressed
ZolmitriptanZolmitriptan12suppressed
AzithromycinAzithromycin11suppressed
Hydralazine HclHydralazine Hcl11suppressed
Hydroxyzine PamoateHydroxyzine Pamoate11suppressed
NitroglycerinNitroglycerin11suppressed
Oxybutynin Chloride ErOxybutynin Chloride11suppressed
XareltoRivaroxaban11suppressed

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