Healthcare provider profile · identity verified

Katrina Ruth Hammel, M.D.

Internal Medicine · WINONA, MN · NPI 1780894527

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	858	196
Omeprazole	Omeprazole	617	136
Metoprolol Succinate	Metoprolol Succinate	613	135
Levothyroxine Sodium	Levothyroxine Sodium	595	121
Amlodipine Besylate	Amlodipine Besylate	554	131
Losartan Potassium	Losartan Potassium	516	122
Furosemide	Furosemide	486	113
Lisinopril	Lisinopril	426	104
Gabapentin	Gabapentin	398	90
Eliquis	Apixaban	308	60
Potassium Chloride	Potassium Chloride	299	57
Sertraline Hcl	Sertraline Hcl	273	55
Rosuvastatin Calcium	Rosuvastatin Calcium	225	63
Pantoprazole Sodium	Pantoprazole Sodium	222	56
Simvastatin	Simvastatin	208	48
Metformin Hcl	Metformin Hcl	203	46
Hydrochlorothiazide	Hydrochlorothiazide	200	46
Tamsulosin Hcl	Tamsulosin Hcl	198	48
Tramadol Hcl	Tramadol Hcl	192	45
Arexvy	Rsvpref3 Antigen/As01e/Pf	179	179
Prednisone	Prednisone	175	62
Duloxetine Hcl	Duloxetine Hcl	173	41
Metoprolol Tartrate	Metoprolol Tartrate	173	41
Trazodone Hcl	Trazodone Hcl	173	60
Allopurinol	Allopurinol	170	44
Mirtazapine	Mirtazapine	166	28
Warfarin Sodium	Warfarin Sodium	159	32
Famotidine	Famotidine	145	36
Clopidogrel	Clopidogrel Bisulfate	143	32
Boostrix Tdap	Diphth,pertuss(Acell),tet Vac	138	138
Bupropion Xl	Bupropion Hcl	129	22
Albuterol Sulfate Hfa	Albuterol Sulfate	121	64
Hydrocodone-Acetaminophen	Hydrocodone/Acetaminophen	121	23
Metformin Hcl Er	Metformin Hcl	119	33
Lantus Solostar	Insulin Glargine,hum.Rec.Anlog	116	39
Shingrix	Varicella-Zoster Ge/As01b/Pf	116	76
Montelukast Sodium	Montelukast Sodium	112	26
Fluticasone Propionate	Fluticasone Propionate	108	36
Trulicity	Dulaglutide	108	18
Alendronate Sodium	Alendronate Sodium	107	27
Citalopram Hbr	Citalopram Hydrobromide	104	24
Ozempic	Semaglutide	103	20
Venlafaxine Hcl Er	Venlafaxine Hcl	102	15
Hydralazine Hcl	Hydralazine Hcl	100	21
Pregabalin	Pregabalin	100	26
Spironolactone	Spironolactone	100	27
Atenolol	Atenolol	95	16
Jardiance	Empagliflozin	95	27
Pravastatin Sodium	Pravastatin Sodium	95	17
Buspirone Hcl	Buspirone Hcl	94	24
Fluoxetine Hcl	Fluoxetine Hcl	89	17
Oxycodone Hcl	Oxycodone Hcl	86	30
Hydroxyzine Hcl	Hydroxyzine Hcl	80	18
Carbidopa-Levodopa	Carbidopa/Levodopa	78	suppressed
Carvedilol	Carvedilol	78	22
Levetiracetam	Levetiracetam	77	suppressed
Autoshield Duo Pen Needle	Pen Needle,dual Safety,diabetc	74	15
Escitalopram Oxalate	Escitalopram Oxalate	73	14
Olanzapine	Olanzapine	73	11
Bumetanide	Bumetanide	72	18
Donepezil Hcl	Donepezil Hcl	72	14
Torsemide	Torsemide	72	22
Isosorbide Mononitrate Er	Isosorbide Mononitrate	70	25
Doxazosin Mesylate	Doxazosin Mesylate	68	12
Ezetimibe	Ezetimibe	68	19
Mounjaro	Tirzepatide	68	14
Celecoxib	Celecoxib	65	17
Trelegy Ellipta	Fluticasone/Umeclidin/Vilanter	65	12
Baclofen	Baclofen	63	11
Finasteride	Finasteride	63	14
Quetiapine Fumarate	Quetiapine Fumarate	61	19
Farxiga	Dapagliflozin Propanediol	59	suppressed
Chlorthalidone	Chlorthalidone	57	16
Fluticasone-Salmeterol	Fluticasone Propion/Salmeterol	56	16
Pramipexole Dihydrochloride	Pramipexole Di-Hcl	56	15
Aripiprazole	Aripiprazole	55	suppressed
Diltiazem 24hr Er (Cd)	Diltiazem Hcl	55	17
Glipizide Er	Glipizide	54	20
Nitroglycerin	Nitroglycerin	50	29
Basaglar Kwikpen U-100	Insulin Glargine,hum.Rec.Anlog	49	suppressed
Triamcinolone Acetonide	Triamcinolone Acetonide	48	31
Azithromycin	Azithromycin	47	23
Breo Ellipta	Fluticasone/Vilanterol	46	suppressed
Meloxicam	Meloxicam	45	12
Lamotrigine	Lamotrigine	43	suppressed
Humalog Kwikpen U-100	Insulin Lispro	41	19
Novolog Flexpen	Insulin Aspart	41	14
Ventolin Hfa	Albuterol Sulfate	41	27
Clonazepam	Clonazepam	40	11
Ropinirole Hcl	Ropinirole Hcl	40	suppressed
Cyclobenzaprine Hcl	Cyclobenzaprine Hcl	39	20
Midodrine Hcl	Midodrine Hcl	39	suppressed
Paroxetine Hcl	Paroxetine Hcl	39	suppressed
Fenofibrate	Fenofibrate Nanocrystallized	37	suppressed
Hydromorphone Hcl	Hydromorphone Hcl	37	suppressed
Fentanyl	Fentanyl	36	suppressed
Ramipril	Ramipril	35	suppressed
Estradiol	Estradiol	34	11
Nystatin	Nystatin	34	18
Oxybutynin Chloride Er	Oxybutynin Chloride	34	suppressed
Esomeprazole Magnesium	Esomeprazole Magnesium	33	suppressed
Propranolol Hcl	Propranolol Hcl	33	suppressed
Divalproex Sodium Er	Divalproex Sodium	32	suppressed
Glimepiride	Glimepiride	32	11
Oxybutynin Chloride	Oxybutynin Chloride	32	suppressed
Glipizide	Glipizide	31	suppressed
Myrbetriq	Mirabegron	31	suppressed
Sucralfate	Sucralfate	31	suppressed
Testosterone Cypionate	Testosterone Cypionate	31	suppressed
Xarelto	Rivaroxaban	31	suppressed
Methadone Hcl	Methadone Hcl	30	suppressed
Cholestyramine	Cholestyramine (With Sugar)	29	suppressed
Hydrocortisone	Hydrocortisone	29	suppressed
Latanoprost	Latanoprost	29	suppressed
Memantine Hcl	Memantine Hcl	29	suppressed
Cephalexin	Cephalexin	28	22
Morphine Sulfate	Morphine Sulfate	28	suppressed
Nystop	Nystatin	27	suppressed
Rivastigmine	Rivastigmine Tartrate	27	suppressed
Sulfamethoxazole-Trimethoprim	Sulfamethoxazole/Trimethoprim	27	12
Fluconazole	Fluconazole	26	18
Methocarbamol	Methocarbamol	26	suppressed
Valacyclovir	Valacyclovir Hcl	26	suppressed
Advair Hfa	Fluticasone Propion/Salmeterol	25	suppressed
Amoxicillin	Amoxicillin	25	13
Digoxin	Digoxin	25	suppressed
Ipratropium-Albuterol	Ipratropium/Albuterol Sulfate	25	suppressed
Lorazepam	Lorazepam	25	14
Budesonide-Formoterol Fumarate	Budesonide/Formoterol Fumarate	24	suppressed
Diclofenac Sodium	Diclofenac Sodium	24	suppressed
Ketoconazole	Ketoconazole	24	suppressed
Amantadine	Amantadine Hcl	23	suppressed
Entresto	Sacubitril/Valsartan	23	suppressed
Tizanidine Hcl	Tizanidine Hcl	23	suppressed
Fludrocortisone Acetate	Fludrocortisone Acetate	22	suppressed
Acyclovir	Acyclovir	21	suppressed
Budesonide	Budesonide	21	suppressed
Lactulose	Lactulose	21	suppressed
Morphine Sulfate Er	Morphine Sulfate	21	suppressed
Nifedipine Er	Nifedipine	21	suppressed
Lidocaine	Lidocaine	20	suppressed
Ondansetron Hcl	Ondansetron Hcl	20	suppressed
Propranolol Hcl Er	Propranolol Hcl	20	suppressed
Acetic Acid	Acetic Acid	19	suppressed
Amoxicillin-Clavulanate Potass	Amoxicillin/Potassium Clav	19	19
Carbamazepine	Carbamazepine	19	suppressed
Clotrimazole-Betamethasone	Clotrimazole/Betamethasone Dip	19	suppressed
Diphenoxylate-Atropine	Diphenoxylate Hcl/Atropine	19	suppressed
Hydroxychloroquine Sulfate	Hydroxychloroquine Sulfate	19	suppressed
Repatha Syringe	Evolocumab	19	suppressed
Spiriva Handihaler	Tiotropium Bromide	19	suppressed
Austedo	Deutetrabenazine	18	suppressed
Carbamazepine Er	Carbamazepine	18	suppressed
Diazepam	Diazepam	18	suppressed
Folic Acid	Folic Acid	18	suppressed
Incruse Ellipta	Umeclidinium Bromide	18	suppressed
Labetalol Hcl	Labetalol Hcl	18	suppressed
Loperamide	Loperamide Hcl	18	suppressed
Phenobarbital	Phenobarbital	18	suppressed
Bupropion Hcl Sr	Bupropion Hcl	17	suppressed
Clonidine Hcl	Clonidine Hcl	17	suppressed
Colchicine	Colchicine	17	suppressed
Creon	Lipase/Protease/Amylase	17	suppressed
Lisinopril-Hydrochlorothiazide	Lisinopril/Hydrochlorothiazide	17	suppressed
Rybelsus	Semaglutide	17	suppressed
Divalproex Sodium	Divalproex Sodium	16	suppressed
Doxycycline Monohydrate	Doxycycline Monohydrate	16	15
Gavilyte-G	Peg3350/Sod Sulf,bicarb,cl/Kcl	16	16
Levocetirizine Dihydrochloride	Levocetirizine Dihydrochloride	16	suppressed
Metoclopramide Hcl	Metoclopramide Hcl	16	suppressed
Pioglitazone Hcl	Pioglitazone Hcl	16	suppressed
Risperidone	Risperidone	16	suppressed
Armour Thyroid	Thyroid,pork	15	suppressed
Brilinta	Ticagrelor	15	suppressed
Fenofibrate	Fenofibrate	15	suppressed
Nortriptyline Hcl	Nortriptyline Hcl	15	suppressed
Prazosin Hcl	Prazosin Hcl	15	suppressed
Timolol Maleate	Timolol Maleate	15	suppressed
Zonisamide	Zonisamide	15	suppressed
Dorzolamide-Timolol	Dorzolamide Hcl/Timolol Maleat	14	suppressed
Oxycontin	Oxycodone Hcl	14	suppressed
Zolpidem Tartrate	Zolpidem Tartrate	14	suppressed
Aspirin-Dipyridamole Er	Aspirin/Dipyridamole	13	suppressed
Bisoprolol Fumarate	Bisoprolol Fumarate	13	suppressed
Brimonidine Tartrate	Brimonidine Tartrate	13	suppressed
Cilostazol	Cilostazol	13	suppressed
Desvenlafaxine Succinate Er	Desvenlafaxine Succinate	13	suppressed
Dicyclomine Hcl	Dicyclomine Hcl	13	suppressed
Methenamine Hippurate	Methenamine Hippurate	13	suppressed
Nitrofurantoin Mono-Macro	Nitrofurantoin Monohyd/M-Cryst	13	suppressed
Ranolazine Er	Ranolazine	13	suppressed
Scopolamine	Scopolamine	13	suppressed
Selegiline Hcl	Selegiline Hcl	13	suppressed
Wixela Inhub	Fluticasone Propion/Salmeterol	13	suppressed
Carbidopa-Levodopa Er	Carbidopa/Levodopa	12	suppressed
Clobetasol Propionate	Clobetasol Propionate	12	suppressed
Comfort Ez Pen Needle	Pen Needle, Diabetic	12	suppressed
Cyclosporine	Cyclosporine	12	suppressed
Diltiazem 24hr Er	Diltiazem Hcl	12	suppressed
Doxycycline Hyclate	Doxycycline Hyclate	12	suppressed
Enbrel Sureclick	Etanercept	12	suppressed
Icosapent Ethyl	Icosapent Ethyl	12	suppressed
Meclizine Hcl	Meclizine Hcl	12	suppressed
Metolazone	Metolazone	12	suppressed
Mometasone Furoate	Mometasone Furoate	12	suppressed
Oxcarbazepine	Oxcarbazepine	12	suppressed
Suboxone	Buprenorphine Hcl/Naloxone Hcl	12	suppressed
Erythromycin	Erythromycin Base	11	suppressed
Fenofibrate	Fenofibrate,micronized	11	suppressed
Fesoterodine Fumarate Er	Fesoterodine Fumarate	11	suppressed
Fiasp Flextouch	Insulin Aspart (Niacinamide)	11	suppressed
Insulin Glargine-Yfgn	Insulin Glargine-Yfgn	11	suppressed
Januvia	Sitagliptin Phosphate	11	suppressed
Losartan-Hydrochlorothiazide	Losartan/Hydrochlorothiazide	11	suppressed
M-Natal Plus	Pnv,calcium 72/Iron/Folic Acid	11	suppressed
Methotrexate	Methotrexate Sodium	11	suppressed
Naltrexone Hcl	Naltrexone Hcl	11	suppressed
Tradjenta	Linagliptin	11	suppressed
Triamterene-Hydrochlorothiazid	Triamterene/Hydrochlorothiazid	11	suppressed
Trintellix	Vortioxetine Hydrobromide	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

Full methodology · Questions & answers · Report a possible error