Healthcare provider profile · identity verified

Sonja K. Olsen, M.D.

Allopathic & Osteopathic Physicians|Internal Medicine|Gastroenterology · WEST PALM BEACH, FL · NPI 1124221882

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 Sonja K. Olsen, M.D. received $150,078.41 in general payments during 2025 across 125 reported records.

Madrigal Pharmaceuticals accounted for 96.5% of that reported general-payment amount.

The Open Payments records used for this analysis explicitly named 12 associated products.

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

Madrigal Pharmaceuticals reported payments to this doctor in 2025. Across the 2025 Open Payments General Payment records loaded for this analysis, that same reporting entity reported REZDIFFRA as an associated drug or biological on 75650 records involving 19195 distinct recipient NPIs. Public Medicare Part D data also shows 13 claims for Rezdiffra by this doctor in 2024.

Salix Pharmaceuticals, a division of Bausch Health US, LLC reported payments to this doctor in 2025. Across the 2025 Open Payments General Payment records loaded for this analysis, that same reporting entity reported XIFAXAN as an associated drug or biological on 101901 records involving 33018 distinct recipient NPIs. Public Medicare Part D data also shows 15 claims for Xifaxan by this doctor in 2024.

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

Payment overview · 2025

General Payments

$150,078.41

125 reported records · 10 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
Madrigal Pharmaceuticals Unresolved — no canonical attribution shown $144,798.3696.5%1052025
ABBVIE INC. Unresolved — no canonical attribution shown $4,971.263.3%102025
Ipsen Biopharmaceuticals, Inc Unresolved — no canonical attribution shown $67.650.1%22025
Novo Nordisk Inc Unresolved — no canonical attribution shown $65.590.0%12025
Salix Pharmaceuticals, a division of Bausch Health US, LLC Unresolved — no canonical attribution shown $46.230.0%22025
Takeda Pharmaceuticals U.S.A., Inc. Unresolved — no canonical attribution shown $32.070.0%12025
Mallinckrodt Hospital Products Inc. Unresolved — no canonical attribution shown $29.430.0%12025
Lilly USA, LLC Unresolved — no canonical attribution shown $24.370.0%12025
Janssen Biotech, Inc. Unresolved — no canonical attribution shown $22.210.0%12025
Intercept Pharmaceuticals, Inc. Unresolved — no canonical attribution shown $21.240.0%12025

What were the payments for?

Payment categories

CategoryAmountRecords
Compensation for services other than consulting, including serving as faculty or as a speaker at a venue other than a continuing education program$130,721.5055
Travel and Lodging$9,004.6223
Consulting Fee$7,095.002
Food and Beverage$3,257.2945

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
REZDIFFRA
Normalized: rezdiffra
Drug Madrigal Pharmaceuticals $144,798.36 105 2025
Source payment records
MAVYRET
Normalized: mavyret
Drug ABBVIE INC. $4,725.00 3 2025
Source payment records
SKYRIZI
Normalized: skyrizi
Biological ABBVIE INC. $173.03 3 2025
Source payment records
CREON
Normalized: creon
Drug ABBVIE INC. $73.23 4 2025
Source payment records
LINZESS
Normalized: linzess
Drug ABBVIE INC. $73.23 4 2025
Source payment records
IQIRVO
Normalized: iqirvo
Drug Ipsen Biopharmaceuticals, Inc $67.65 2 2025
Source payment records
XIFAXAN
Normalized: xifaxan
Drug Salix Pharmaceuticals, a division of Bausch Health US, LLC $46.23 2 2025
Source payment records
  • 2025-07-28 · Salix Pharmaceuticals, a division of Bausch Health US, LLC · $24.04 · Open Payments source
  • 2025-11-17 · Salix Pharmaceuticals, a division of Bausch Health US, LLC · $22.19 · Open Payments source
ENTYVIO
Normalized: entyvio
Biological Takeda Pharmaceuticals U.S.A., Inc. $32.07 1 2025
Source payment records
TERLIVAZ
Normalized: terlivaz
Drug Mallinckrodt Hospital Products Inc. $29.43 1 2025
Source payment records
OMVOH
Normalized: omvoh
Drug Lilly USA, LLC $24.37 1 2025
Source payment records
TREMFYA
Normalized: tremfya
Drug Janssen Biotech, Inc. $22.21 1 2025
Source payment records
OCALIVA
Normalized: ocaliva
Drug Intercept Pharmaceuticals, Inc. $21.24 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
REZDIFFRA
rezdiffra
2025 Rezdiffra 2024 13
Beneficiary count suppressed
exact normalized Medicare Part D
XIFAXAN
xifaxan
2025 Xifaxan 2024 15
Beneficiary count suppressed
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
Madrigal Pharmaceuticals
Exact reporting entity; no affiliate inference
2025 REZDIFFRA
open payments reported associated product
CMS Open Payments — General Payments
75650 supporting records · 19195 recipient NPIs · example record 1248227746
Rezdiffra · 2024
Exact normalized brand match · 1 Part D row
13 suppressed by CMS
Salix Pharmaceuticals, a division of Bausch Health US, LLC
Exact reporting entity; no affiliate inference
2025 XIFAXAN
open payments reported associated product
CMS Open Payments — General Payments
101901 supporting records · 33018 recipient NPIs · example record 1231775337
Xifaxan · 2024
Exact normalized brand match · 1 Part D row
15 suppressed by CMS

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
Sod Sulf-Potass Sulf-Mag SulfSodium, Potassium,mag Sulfates4039
SpironolactoneSpironolactone2612
Pantoprazole SodiumPantoprazole Sodium2212
FurosemideFurosemide20suppressed
PrednisonePrednisone19suppressed
Ondansetron OdtOndansetron1813
BumetanideBumetanide17suppressed
XifaxanRifaximin15suppressed
FamotidineFamotidine14suppressed
Esomeprazole MagnesiumEsomeprazole Magnesium13suppressed
LactuloseLactulose13suppressed
RezdiffraResmetirom13suppressed
Ciprofloxacin HclCiprofloxacin Hcl11suppressed
OmeprazoleOmeprazole11suppressed

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 $150,078.41 · 125 records Madrigal Pharmaceuticals CREON, ENTYVIO, IQIRVO, LINZESS, MAVYRET, OCALIVA, OMVOH, REZDIFFRA, SKYRIZI, TERLIVAZ, TREMFYA, XIFAXAN 2
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