Healthcare provider profile · identity verified

Christopher William Nau, MD

Internal Medicine · CHILLICOTHE, IL · NPI 1104023092

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

Brand	Generic	Claims	Beneficiaries
Atorvastatin Calcium	Atorvastatin Calcium	425	143
Hydrocodone-Acetaminophen	Hydrocodone/Acetaminophen	305	55
Amlodipine Besylate	Amlodipine Besylate	286	90
Levothyroxine Sodium	Levothyroxine Sodium	278	92
Lisinopril	Lisinopril	245	78
Losartan Potassium	Losartan Potassium	241	72
Lorazepam	Lorazepam	197	40
Omeprazole	Omeprazole	169	60
Hydrochlorothiazide	Hydrochlorothiazide	163	53
Metoprolol Succinate	Metoprolol Succinate	145	45
Gabapentin	Gabapentin	134	46
Metformin Hcl	Metformin Hcl	132	44
Sertraline Hcl	Sertraline Hcl	131	41
Alprazolam	Alprazolam	128	30
Rosuvastatin Calcium	Rosuvastatin Calcium	127	40
Albuterol Sulfate Hfa	Albuterol Sulfate	126	41
Simvastatin	Simvastatin	124	40
Tamsulosin Hcl	Tamsulosin Hcl	122	41
Pantoprazole Sodium	Pantoprazole Sodium	110	36
Metoprolol Tartrate	Metoprolol Tartrate	98	26
Tramadol Hcl	Tramadol Hcl	96	31
Montelukast Sodium	Montelukast Sodium	83	28
Venlafaxine Hcl Er	Venlafaxine Hcl	81	24
Fluticasone Propionate	Fluticasone Propionate	76	26
Trazodone Hcl	Trazodone Hcl	73	29
Furosemide	Furosemide	71	29
Meloxicam	Meloxicam	68	25
Cyclobenzaprine Hcl	Cyclobenzaprine Hcl	64	17
Escitalopram Oxalate	Escitalopram Oxalate	64	25
Glimepiride	Glimepiride	60	20
Clopidogrel	Clopidogrel Bisulfate	59	20
Warfarin Sodium	Warfarin Sodium	57	19
Jardiance	Empagliflozin	52	17
Metformin Hcl Er	Metformin Hcl	52	19
Allopurinol	Allopurinol	51	19
Buspirone Hcl	Buspirone Hcl	51	16
Pravastatin Sodium	Pravastatin Sodium	50	14
Tizanidine Hcl	Tizanidine Hcl	49	19
Alendronate Sodium	Alendronate Sodium	48	15
Ezetimibe	Ezetimibe	47	13
Potassium Chloride	Potassium Chloride	46	19
Prednisone	Prednisone	46	33
Citalopram Hbr	Citalopram Hydrobromide	45	16
Glipizide Er	Glipizide	45	suppressed
Clonazepam	Clonazepam	43	13
Duloxetine Hcl	Duloxetine Hcl	42	14
Carvedilol	Carvedilol	41	14
Oxycodone Hcl	Oxycodone Hcl	40	suppressed
Amitriptyline Hcl	Amitriptyline Hcl	39	16
Eliquis	Apixaban	38	20
Ibuprofen	Ibuprofen	36	suppressed
Losartan-Hydrochlorothiazide	Losartan/Hydrochlorothiazide	36	suppressed
Xarelto	Rivaroxaban	36	12
Dextroamphetamine-Amphetamine	Dextroamphetamine/Amphetamine	35	suppressed
Ozempic	Semaglutide	35	suppressed
Bupropion Xl	Bupropion Hcl	32	14
Atenolol	Atenolol	31	suppressed
Diltiazem 24hr Er (Cd)	Diltiazem Hcl	31	suppressed
Pioglitazone Hcl	Pioglitazone Hcl	31	suppressed
Zolpidem Tartrate	Zolpidem Tartrate	31	15
Lantus Solostar	Insulin Glargine,hum.Rec.Anlog	30	11
Diazepam	Diazepam	29	suppressed
Finasteride	Finasteride	29	suppressed
Lovastatin	Lovastatin	29	suppressed
Oxycodone-Acetaminophen	Oxycodone Hcl/Acetaminophen	29	suppressed
Symbicort	Budesonide/Formoterol Fumarate	28	suppressed
Oxybutynin Chloride Er	Oxybutynin Chloride	27	13
Spironolactone	Spironolactone	27	11
Triamcinolone Acetonide	Triamcinolone Acetonide	27	16
Cephalexin	Cephalexin	26	24
Naproxen	Naproxen	26	11
Ropinirole Hcl	Ropinirole Hcl	26	suppressed
Triamterene-Hydrochlorothiazid	Triamterene/Hydrochlorothiazid	25	12
Fluoxetine Hcl	Fluoxetine Hcl	24	11
Trelegy Ellipta	Fluticasone/Umeclidin/Vilanter	24	suppressed
Glipizide	Glipizide	23	suppressed
Amlodipine Besylate-Benazepril	Amlodipine Besylate/Benazepril	22	suppressed
Irbesartan	Irbesartan	20	suppressed
Pregabalin	Pregabalin	19	suppressed
Propranolol Hcl	Propranolol Hcl	19	suppressed
Spiriva Handihaler	Tiotropium Bromide	19	suppressed
Esomeprazole Magnesium	Esomeprazole Magnesium	18	suppressed
Fluticasone-Salmeterol	Fluticasone Propion/Salmeterol	18	suppressed
Paroxetine Hcl	Paroxetine Hcl	18	suppressed
Pramipexole Dihydrochloride	Pramipexole Di-Hcl	18	suppressed
Sumatriptan Succinate	Sumatriptan Succinate	18	suppressed
Basaglar Kwikpen U-100	Insulin Glargine,hum.Rec.Anlog	17	suppressed
Hydroxyzine Hcl	Hydroxyzine Hcl	17	suppressed
Klor-Con M20	Potassium Chloride	17	suppressed
Ondansetron Odt	Ondansetron	17	suppressed
Topiramate	Topiramate	17	suppressed
Azithromycin	Azithromycin	16	suppressed
Lisinopril-Hydrochlorothiazide	Lisinopril/Hydrochlorothiazide	16	suppressed
Mounjaro	Tirzepatide	16	suppressed
Valacyclovir	Valacyclovir Hcl	16	suppressed
Bisoprolol-Hydrochlorothiazide	Bisoprolol/Hydrochlorothiazide	15	suppressed
Olmesartan Medoxomil	Olmesartan Medoxomil	15	suppressed
Ondansetron Hcl	Ondansetron Hcl	15	suppressed
Tradjenta	Linagliptin	15	suppressed
Acetaminophen-Codeine	Acetaminophen With Codeine	14	suppressed
Doxazosin Mesylate	Doxazosin Mesylate	14	suppressed
Enalapril Maleate	Enalapril Maleate	14	suppressed
Fenofibrate	Fenofibrate	14	suppressed
Isosorbide Mononitrate Er	Isosorbide Mononitrate	14	suppressed
Myrbetriq	Mirabegron	14	suppressed
Rybelsus	Semaglutide	14	suppressed
Dextroamphetamine-Amphet Er	Dextroamphetamine/Amphetamine	13	suppressed
Diclofenac Sodium	Diclofenac Sodium	13	suppressed
Fenofibrate	Fenofibrate Nanocrystallized	13	suppressed
Flecainide Acetate	Flecainide Acetate	13	suppressed
Fluconazole	Fluconazole	13	suppressed
Mirtazapine	Mirtazapine	13	suppressed
Pulmicort Flexhaler	Budesonide	13	suppressed
Ultra-Fine Short Pen Needle	Pen Needle, Diabetic	13	suppressed
Baclofen	Baclofen	12	suppressed
Brilinta	Ticagrelor	12	suppressed
Chlorthalidone	Chlorthalidone	12	suppressed
Donepezil Hcl	Donepezil Hcl	12	suppressed
Famotidine	Famotidine	12	suppressed
Invega Sustenna	Paliperidone Palmitate	12	suppressed
Nitrofurantoin Mono-Macro	Nitrofurantoin Monohyd/M-Cryst	12	11
Vitamin D2	Ergocalciferol (Vitamin D2)	12	suppressed
Amoxicillin	Amoxicillin	11	suppressed
Benazepril Hcl	Benazepril Hcl	11	suppressed
Clindamycin Hcl	Clindamycin Hcl	11	suppressed
Incruse Ellipta	Umeclidinium Bromide	11	suppressed
Klor-Con M10	Potassium Chloride	11	suppressed
Ramipril	Ramipril	11	suppressed
Ventolin Hfa	Albuterol Sulfate	11	suppressed
Wixela Inhub	Fluticasone Propion/Salmeterol	11	suppressed

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.

Year	General Payments	Main payer	Explicit products	Company overlaps	Part D coverage
2025	—	—	—	—	—
2024	—	—	—	—	Complete

Questions to ask

Questions you could discuss with your doctor

Are there reasonable alternatives I should understand when we discuss treatment options?
How should I interpret the industry-payment records shown here in the context of my care?

These are general questions generated from reviewed templates. They are not personalized medical advice.

Sources and limitations

How to read this page

Payment and Medicare prescribing data can cover different years; every comparison shows both years explicitly.
Part D does not represent a doctor’s entire practice; it excludes many patients and is subject to CMS public-release thresholds.
Company–drug relationships must have an auditable source, a precise relationship type, and a valid evidence period. Unresolved mappings are not published.
Generic drug claims are not attributed to a specific manufacturer without manufacturer-level evidence.
When a source extract is incomplete, missing rows are never treated as proof of no payments or no prescriptions.

Loaded source releases

Dataset	Year	Publication	Source
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

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