Healthcare provider profile · identity verified

Mark A Thomas, MD

Internal Medicine · TOPEKA, KS · NPI 1629086277

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	879	243
Amlodipine Besylate	Amlodipine Besylate	725	199
Levothyroxine Sodium	Levothyroxine Sodium	519	129
Losartan Potassium	Losartan Potassium	469	130
Omeprazole	Omeprazole	332	87
Rosuvastatin Calcium	Rosuvastatin Calcium	263	79
Simvastatin	Simvastatin	254	69
Metformin Hcl Er	Metformin Hcl	253	70
Gabapentin	Gabapentin	242	77
Lisinopril	Lisinopril	200	53
Tamsulosin Hcl	Tamsulosin Hcl	187	51
Metoprolol Succinate	Metoprolol Succinate	176	46
Hydrochlorothiazide	Hydrochlorothiazide	162	48
Sertraline Hcl	Sertraline Hcl	158	46
Potassium Chloride	Potassium Chloride	135	41
Losartan-Hydrochlorothiazide	Losartan/Hydrochlorothiazide	132	36
Fluticasone Propionate	Fluticasone Propionate	129	41
Pantoprazole Sodium	Pantoprazole Sodium	122	38
Carvedilol	Carvedilol	112	32
Allopurinol	Allopurinol	105	28
Finasteride	Finasteride	104	24
Albuterol Sulfate Hfa	Albuterol Sulfate	103	45
Tramadol Hcl	Tramadol Hcl	98	25
Ozempic	Semaglutide	97	18
Duloxetine Hcl	Duloxetine Hcl	91	28
Montelukast Sodium	Montelukast Sodium	91	25
Atenolol	Atenolol	83	24
Metoprolol Tartrate	Metoprolol Tartrate	79	20
Metformin Hcl	Metformin Hcl	78	18
Pravastatin Sodium	Pravastatin Sodium	78	18
Escitalopram Oxalate	Escitalopram Oxalate	69	19
Methylprednisolone	Methylprednisolone	61	54
Jardiance	Empagliflozin	59	14
Ropinirole Hcl	Ropinirole Hcl	58	12
Furosemide	Furosemide	52	21
Amlodipine Besylate-Benazepril	Amlodipine Besylate/Benazepril	50	13
Synthroid	Levothyroxine Sodium	50	11
Triamcinolone Acetonide	Triamcinolone Acetonide	49	32
Spironolactone	Spironolactone	48	13
Tizanidine Hcl	Tizanidine Hcl	48	27
Fluoxetine Hcl	Fluoxetine Hcl	47	13
Meloxicam	Meloxicam	47	22
Citalopram Hbr	Citalopram Hydrobromide	46	13
Trazodone Hcl	Trazodone Hcl	45	14
Famotidine	Famotidine	44	suppressed
Glipizide Er	Glipizide	44	14
Fenofibrate	Fenofibrate Nanocrystallized	43	suppressed
Irbesartan	Irbesartan	43	12
Olmesartan Medoxomil	Olmesartan Medoxomil	43	12
Clopidogrel	Clopidogrel Bisulfate	39	13
Glipizide	Glipizide	38	suppressed
Venlafaxine Hcl Er	Venlafaxine Hcl	37	suppressed
Breo Ellipta	Fluticasone/Vilanterol	35	suppressed
Meclizine Hcl	Meclizine Hcl	34	22
Torsemide	Torsemide	34	11
Pioglitazone Hcl	Pioglitazone Hcl	33	suppressed
Bisoprolol-Hydrochlorothiazide	Bisoprolol/Hydrochlorothiazide	32	suppressed
Celecoxib	Celecoxib	32	suppressed
Cephalexin	Cephalexin	32	27
Xarelto	Rivaroxaban	32	suppressed
Triamterene-Hydrochlorothiazid	Triamterene/Hydrochlorothiazid	31	suppressed
Trulicity	Dulaglutide	31	suppressed
Lisinopril-Hydrochlorothiazide	Lisinopril/Hydrochlorothiazide	30	suppressed
Oxybutynin Chloride	Oxybutynin Chloride	30	suppressed
Tolterodine Tartrate Er	Tolterodine Tartrate	30	suppressed
Bupropion Xl	Bupropion Hcl	29	suppressed
Clonidine Hcl	Clonidine Hcl	29	suppressed
Farxiga	Dapagliflozin Propanediol	29	suppressed
Warfarin Sodium	Warfarin Sodium	29	suppressed
Basaglar Kwikpen U-100	Insulin Glargine,hum.Rec.Anlog	28	suppressed
Ezetimibe	Ezetimibe	28	suppressed
Hydrocodone-Acetaminophen	Hydrocodone/Acetaminophen	28	16
Lantus Solostar	Insulin Glargine,hum.Rec.Anlog	27	suppressed
Acyclovir	Acyclovir	26	suppressed
Amlodipine-Atorvastatin	Amlodipine/Atorvastatin	25	suppressed
Donepezil Hcl	Donepezil Hcl	25	suppressed
Enalapril Maleate	Enalapril Maleate	25	suppressed
Klor-Con M20	Potassium Chloride	25	suppressed
Candesartan-Hydrochlorothiazid	Candesartan/Hydrochlorothiazid	24	suppressed
Mirtazapine	Mirtazapine	24	suppressed
Doxazosin Mesylate	Doxazosin Mesylate	21	suppressed
Diltiazem 24hr Er (Cd)	Diltiazem Hcl	20	suppressed
Levetiracetam	Levetiracetam	20	suppressed
Nano 2nd Gen Pen Needle	Pen Needle, Diabetic	20	suppressed
Paxlovid	Nirmatrelvir/Ritonavir	20	19
Glimepiride	Glimepiride	19	suppressed
Terazosin Hcl	Terazosin Hcl	19	suppressed
Zolpidem Tartrate	Zolpidem Tartrate	19	suppressed
Amoxicillin-Clavulanate Potass	Amoxicillin/Potassium Clav	18	17
Doxepin Hcl	Doxepin Hcl	18	suppressed
Nitrofurantoin Mono-Macro	Nitrofurantoin Monohyd/M-Cryst	18	15
Azelastine Hcl	Azelastine Hcl	17	suppressed
Benazepril-Hydrochlorothiazide	Benazepril/Hydrochlorothiazide	17	suppressed
Chlorthalidone	Chlorthalidone	17	suppressed
Doxycycline Hyclate	Doxycycline Hyclate	17	16
Oxybutynin Chloride Er	Oxybutynin Chloride	17	suppressed
Pregabalin	Pregabalin	17	suppressed
Alendronate Sodium	Alendronate Sodium	16	suppressed
Amlodipine-Valsartan	Amlodipine Besylate/Valsartan	16	suppressed
Valacyclovir	Valacyclovir Hcl	16	suppressed
Varenicline Tartrate	Varenicline Tartrate	16	suppressed
Ammonium Lactate	Ammonium Lactate	15	11
Eliquis	Apixaban	15	suppressed
Amitriptyline Hcl	Amitriptyline Hcl	14	suppressed
Amlodipine-Olmesartan	Amlodipine Bes/Olmesartan Med	14	suppressed
Baclofen	Baclofen	14	suppressed
Dropsafe Prep Pads	Alcohol Antiseptic Pads	14	suppressed
Felodipine Er	Felodipine	14	suppressed
Irbesartan-Hydrochlorothiazide	Irbesartan/Hydrochlorothiazide	14	suppressed
Lubiprostone	Lubiprostone	14	suppressed
Mounjaro	Tirzepatide	14	suppressed
Paroxetine Hcl	Paroxetine Hcl	14	suppressed
Propranolol Hcl	Propranolol Hcl	14	suppressed
Valsartan-Hydrochlorothiazide	Valsartan/Hydrochlorothiazide	14	suppressed
Wixela Inhub	Fluticasone Propion/Salmeterol	14	suppressed
Bisoprolol Fumarate	Bisoprolol Fumarate	13	suppressed
Hydralazine Hcl	Hydralazine Hcl	13	suppressed
Atenolol-Chlorthalidone	Atenolol/Chlorthalidone	12	suppressed
Gemfibrozil	Gemfibrozil	12	suppressed
Ibuprofen	Ibuprofen	12	suppressed
Memantine Hcl	Memantine Hcl	12	suppressed
Novolog Flexpen	Insulin Aspart	12	suppressed
Sildenafil Citrate	Sildenafil Citrate	12	suppressed
Spiriva Handihaler	Tiotropium Bromide	12	suppressed
Sumatriptan Succinate	Sumatriptan Succinate	12	suppressed
Ultra-Fine Mini Pen Needle	Pen Needle, Diabetic	12	suppressed
Welchol	Colesevelam Hcl	12	suppressed
Alprazolam	Alprazolam	11	suppressed
Esomeprazole Magnesium	Esomeprazole Magnesium	11	suppressed
Nifedipine Er	Nifedipine	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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