Payment overview · 2025
General Payments
$429.06
23 reported records · 10 companies
Healthcare provider profile · identity verified
Mark A Castellaw, MD
Allopathic & Osteopathic Physicians|Internal Medicine · GERMANTOWN, TN · NPI 1114928793
Verified facts
What the public records show
CMS Open Payments records show Mark A Castellaw, MD received $429.06 in general payments during 2025 across 23 reported records.
Novo Nordisk Inc accounted for 28.5% of that reported general-payment amount.
The Open Payments records used for this analysis explicitly named 17 associated products.
A separate comparison found the same explicitly named product in public Medicare Part D data: Jardiance, Mounjaro, Ozempic.
ABBVIE INC. reported payments to this doctor in 2025. Across the 2025 Open Payments General Payment records loaded for this analysis, that same reporting entity reported SYNTHROID as an associated drug or biological on 10655 records involving 4881 distinct recipient NPIs. Public Medicare Part D data also shows 43 claims for Synthroid by this doctor in 2024.
Boehringer Ingelheim Pharmaceuticals, Inc. reported payments to this doctor in 2025. Across the 2025 Open Payments General Payment records loaded for this analysis, that same reporting entity reported JARDIANCE as an associated drug or biological on 123636 records involving 49438 distinct recipient NPIs. Public Medicare Part D data also shows 46 claims for Jardiance by this doctor in 2024.
Lilly USA, 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 JARDIANCE as an associated drug or biological on 47708 records involving 23833 distinct recipient NPIs. Public Medicare Part D data also shows 46 claims for Jardiance by this doctor in 2024.
Lilly USA, 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 MOUNJARO as an associated drug or biological on 186719 records involving 66436 distinct recipient NPIs. Public Medicare Part D data also shows 116 claims for Mounjaro by this doctor in 2024.
Lilly USA, 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 TRULICITY as an associated drug or biological on 71 records involving 57 distinct recipient NPIs. Public Medicare Part D data also shows 19 claims for Trulicity by this doctor in 2024.
Novo Nordisk Inc reported payments to this doctor in 2025. Across the 2025 Open Payments General Payment records loaded for this analysis, that same reporting entity reported Ozempic as an associated drug or biological on 261625 records involving 77793 distinct recipient NPIs. Public Medicare Part D data also shows 222 claims for Ozempic by this doctor in 2024.
PFIZER INC. reported payments to this doctor in 2025. Across the 2025 Open Payments General Payment records loaded for this analysis, that same reporting entity reported ELIQUIS as an associated drug or biological on 87112 records involving 36032 distinct recipient NPIs. Public Medicare Part D data also shows 82 claims for Eliquis by this doctor in 2024.
PFIZER INC. reported payments to this doctor in 2025. Across the 2025 Open Payments General Payment records loaded for this analysis, that same reporting entity reported PAXLOVID as an associated drug or biological on 24465 records involving 15715 distinct recipient NPIs. Public Medicare Part D data also shows 18 claims for Paxlovid by this doctor in 2024.
These records do not establish that a payment influenced prescribing or medical care.
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 company | Canonical company | Amount | Share | Records | Year |
|---|---|---|---|---|---|
| Novo Nordisk Inc | Unresolved — no canonical attribution shown | $122.22 | 28.5% | 6 | 2025 |
| Amgen Inc. | Unresolved — no canonical attribution shown | $71.06 | 16.6% | 5 | 2025 |
| Abbott Laboratories | Unresolved — no canonical attribution shown | $68.07 | 15.9% | 3 | 2025 |
| Lilly USA, LLC | Unresolved — no canonical attribution shown | $31.52 | 7.3% | 2 | 2025 |
| PFIZER INC. | Unresolved — no canonical attribution shown | $31.46 | 7.3% | 2 | 2025 |
| ABBVIE INC. | Unresolved — no canonical attribution shown | $29.98 | 7.0% | 1 | 2025 |
| Seqirus USA Inc | Unresolved — no canonical attribution shown | $29.70 | 6.9% | 1 | 2025 |
| Novartis Pharmaceuticals Corporation | Unresolved — no canonical attribution shown | $16.47 | 3.8% | 1 | 2025 |
| Phathom Pharmaceuticals, Inc. | Unresolved — no canonical attribution shown | $15.09 | 3.5% | 1 | 2025 |
| Boehringer Ingelheim Pharmaceuticals, Inc. | Unresolved — no canonical attribution shown | $13.49 | 3.1% | 1 | 2025 |
What were the payments for?
Payment categories
| Category | Amount | Records |
|---|---|---|
| Food and Beverage | $429.06 | 23 |
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 product | Type | Reported company | Related amount* | Records | Year |
|---|---|---|---|---|---|
| OTEZLA Normalized: otezla |
Drug | Amgen Inc. | $71.06 | 5 | 2025 |
Source payment records
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| REPATHA Normalized: repatha |
Biological | Amgen Inc. | $71.06 | 5 | 2025 |
Source payment records
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| FREESTYLE LIBRE 3 Normalized: freestyle libre 3 |
Device | Abbott Laboratories | $68.07 | 3 | 2025 |
Source payment records
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| Wegovy Normalized: wegovy |
Drug | Novo Nordisk Inc | $63.45 | 4 | 2025 |
Source payment records
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| Ozempic Normalized: ozempic |
Drug | Novo Nordisk Inc | $58.77 | 2 | 2025 |
Source payment records
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| MOUNJARO Normalized: mounjaro |
Drug | Lilly USA, LLC | $31.52 | 2 | 2025 |
Source payment records
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| ZEPBOUND Normalized: zepbound |
Drug | Lilly USA, LLC | $31.52 | 2 | 2025 |
Source payment records
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| ABRYSVO Normalized: abrysvo |
Biological | PFIZER INC. | $31.46 | 2 | 2025 |
Source payment records
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| COMIRNATY Normalized: comirnaty |
Biological | PFIZER INC. | $31.46 | 2 | 2025 |
Source payment records
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| PREVNAR 20 Normalized: prevnar 20 |
Biological | PFIZER INC. | $31.46 | 2 | 2025 |
Source payment records
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| VRAYLAR Normalized: vraylar |
Drug | ABBVIE INC. | $29.98 | 1 | 2025 |
Source payment records
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| Fluad Normalized: fluad |
Biological | Seqirus USA Inc | $29.70 | 1 | 2025 |
Source payment records
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| Flucelvax Normalized: flucelvax |
Biological | Seqirus USA Inc | $29.70 | 1 | 2025 |
Source payment records
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| Rybelsus Normalized: rybelsus |
Drug | Novo Nordisk Inc | $27.72 | 1 | 2025 |
Source payment records
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| LEQVIO Normalized: leqvio |
Drug | Novartis Pharmaceuticals Corporation | $16.47 | 1 | 2025 |
Source payment records
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| VOQUEZNA Normalized: voquezna |
Drug | Phathom Pharmaceuticals, Inc. | $15.09 | 1 | 2025 |
Source payment records
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| JARDIANCE Normalized: jardiance |
Drug | Boehringer Ingelheim Pharmaceuticals, Inc. | $13.49 | 1 | 2025 |
Source payment records
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* 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 product | Payment year | Part D brand | Part D year | Claims | Match method | Source |
|---|---|---|---|---|---|---|
| JARDIANCE jardiance |
2025 | Jardiance | 2024 | 46 | exact normalized | Medicare Part D |
| MOUNJARO mounjaro |
2025 | Mounjaro | 2024 | 116 | exact normalized | Medicare Part D |
| Ozempic ozempic |
2025 | Ozempic | 2024 | 222 | 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 company | Payment year | Drug reported by same entity | Open Payments evidence | Part D | Claims | Beneficiaries |
|---|---|---|---|---|---|---|
| ABBVIE INC. Exact reporting entity; no affiliate inference |
2025 | SYNTHROID open payments reported associated product |
CMS Open Payments — General Payments 10655 supporting records · 4881 recipient NPIs · example record 1201352636 |
Synthroid · 2024 Exact normalized brand match · 1 Part D row |
43 | 11 |
| Boehringer Ingelheim Pharmaceuticals, Inc. Exact reporting entity; no affiliate inference |
2025 | JARDIANCE open payments reported associated product |
CMS Open Payments — General Payments 123636 supporting records · 49438 recipient NPIs · example record 1221811583 |
Jardiance · 2024 Exact normalized brand match · 1 Part D row |
46 | 12 |
| Lilly USA, LLC Exact reporting entity; no affiliate inference |
2025 | JARDIANCE open payments reported associated product |
CMS Open Payments — General Payments 47708 supporting records · 23833 recipient NPIs · example record 1186464557 |
Jardiance · 2024 Exact normalized brand match · 1 Part D row |
46 | 12 |
| Lilly USA, LLC Exact reporting entity; no affiliate inference |
2025 | MOUNJARO open payments reported associated product |
CMS Open Payments — General Payments 186719 supporting records · 66436 recipient NPIs · example record 1186464455 |
Mounjaro · 2024 Exact normalized brand match · 1 Part D row |
116 | 21 |
| Lilly USA, LLC Exact reporting entity; no affiliate inference |
2025 | TRULICITY open payments reported associated product |
CMS Open Payments — General Payments 71 supporting records · 57 recipient NPIs · example record 1186464601 |
Trulicity · 2024 Exact normalized brand match · 1 Part D row |
19 | suppressed by CMS |
| Novo Nordisk Inc Exact reporting entity; no affiliate inference |
2025 | Ozempic open payments reported associated product |
CMS Open Payments — General Payments 261625 supporting records · 77793 recipient NPIs · example record 1188130076 |
Ozempic · 2024 Exact normalized brand match · 1 Part D row |
222 | 58 |
| PFIZER INC. Exact reporting entity; no affiliate inference |
2025 | ELIQUIS open payments reported associated product |
CMS Open Payments — General Payments 87112 supporting records · 36032 recipient NPIs · example record 1228794063 |
Eliquis · 2024 Exact normalized brand match · 1 Part D row |
82 | 27 |
| PFIZER INC. Exact reporting entity; no affiliate inference |
2025 | PAXLOVID open payments reported associated product |
CMS Open Payments — General Payments 24465 supporting records · 15715 recipient NPIs · example record 1228794432 |
Paxlovid · 2024 Exact normalized brand match · 1 Part D row |
18 | 18 |
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 |
|---|---|---|---|
| Amlodipine Besylate | Amlodipine Besylate | 591 | 181 |
| Atorvastatin Calcium | Atorvastatin Calcium | 537 | 154 |
| Levothyroxine Sodium | Levothyroxine Sodium | 535 | 141 |
| Losartan Potassium | Losartan Potassium | 502 | 158 |
| Rosuvastatin Calcium | Rosuvastatin Calcium | 494 | 152 |
| Pantoprazole Sodium | Pantoprazole Sodium | 478 | 135 |
| Ezetimibe | Ezetimibe | 394 | 130 |
| Metoprolol Succinate | Metoprolol Succinate | 318 | 94 |
| Omeprazole | Omeprazole | 316 | 93 |
| Metformin Hcl Er | Metformin Hcl | 306 | 91 |
| Gabapentin | Gabapentin | 303 | 78 |
| Meloxicam | Meloxicam | 286 | 83 |
| Alprazolam | Alprazolam | 265 | 59 |
| Vitamin D2 | Ergocalciferol (Vitamin D2) | 247 | 93 |
| Simvastatin | Simvastatin | 235 | 70 |
| Clonazepam | Clonazepam | 223 | 31 |
| Ozempic | Semaglutide | 222 | 58 |
| Valsartan | Valsartan | 215 | 57 |
| Hydrochlorothiazide | Hydrochlorothiazide | 202 | 62 |
| Tamsulosin Hcl | Tamsulosin Hcl | 194 | 48 |
| Potassium Chloride | Potassium Chloride | 169 | 56 |
| Montelukast Sodium | Montelukast Sodium | 167 | 50 |
| Glimepiride | Glimepiride | 163 | 47 |
| Pravastatin Sodium | Pravastatin Sodium | 163 | 48 |
| Allopurinol | Allopurinol | 160 | 50 |
| Tramadol Hcl | Tramadol Hcl | 160 | 42 |
| Sertraline Hcl | Sertraline Hcl | 155 | 34 |
| Metformin Hcl | Metformin Hcl | 146 | 45 |
| Metoprolol Tartrate | Metoprolol Tartrate | 144 | 45 |
| Furosemide | Furosemide | 140 | 40 |
| Azithromycin | Azithromycin | 116 | 97 |
| Mounjaro | Tirzepatide | 116 | 21 |
| Lorazepam | Lorazepam | 112 | 21 |
| Hydralazine Hcl | Hydralazine Hcl | 101 | 34 |
| Clopidogrel | Clopidogrel Bisulfate | 98 | 35 |
| Lisinopril | Lisinopril | 98 | 31 |
| Olmesartan Medoxomil | Olmesartan Medoxomil | 93 | 26 |
| Valsartan-Hydrochlorothiazide | Valsartan/Hydrochlorothiazide | 93 | 28 |
| Eliquis | Apixaban | 82 | 27 |
| Carvedilol | Carvedilol | 79 | 22 |
| Ciprofloxacin Hcl | Ciprofloxacin Hcl | 74 | 62 |
| Escitalopram Oxalate | Escitalopram Oxalate | 70 | 24 |
| Duloxetine Hcl | Duloxetine Hcl | 66 | 15 |
| Trazodone Hcl | Trazodone Hcl | 66 | 19 |
| Albuterol Sulfate Hfa | Albuterol Sulfate | 64 | 17 |
| Januvia | Sitagliptin Phosphate | 56 | 16 |
| Fluticasone Propionate | Fluticasone Propionate | 55 | 18 |
| Clonidine Hcl | Clonidine Hcl | 54 | 20 |
| Amitriptyline Hcl | Amitriptyline Hcl | 53 | 14 |
| Cyclobenzaprine Hcl | Cyclobenzaprine Hcl | 53 | 18 |
| Zolpidem Tartrate | Zolpidem Tartrate | 53 | 19 |
| Lantus Solostar | Insulin Glargine,hum.Rec.Anlog | 52 | 13 |
| Methylprednisolone | Methylprednisolone | 52 | 38 |
| Losartan-Hydrochlorothiazide | Losartan/Hydrochlorothiazide | 51 | 14 |
| Jardiance | Empagliflozin | 46 | 12 |
| Amoxicillin | Amoxicillin | 44 | 39 |
| Finasteride | Finasteride | 43 | 14 |
| Synthroid | Levothyroxine Sodium | 43 | 11 |
| Atenolol | Atenolol | 42 | 11 |
| Triamcinolone Acetonide | Triamcinolone Acetonide | 42 | 24 |
| Arexvy | Rsvpref3 Antigen/As01e/Pf | 41 | 41 |
| Citalopram Hbr | Citalopram Hydrobromide | 40 | suppressed |
| Clotrimazole-Betamethasone | Clotrimazole/Betamethasone Dip | 40 | 25 |
| Fenofibrate | Fenofibrate Nanocrystallized | 40 | 13 |
| Klor-Con M20 | Potassium Chloride | 40 | 11 |
| Nitrofurantoin | Nitrofurantoin Macrocrystal | 36 | 30 |
| Famotidine | Famotidine | 35 | 14 |
| Hydrocodone-Acetaminophen | Hydrocodone/Acetaminophen | 33 | suppressed |
| Meclizine Hcl | Meclizine Hcl | 32 | 18 |
| Tresiba Flextouch U-200 | Insulin Degludec | 31 | suppressed |
| Alendronate Sodium | Alendronate Sodium | 30 | suppressed |
| Tresiba Flextouch U-100 | Insulin Degludec | 30 | suppressed |
| Nebivolol Hcl | Nebivolol Hcl | 27 | suppressed |
| Toujeo Solostar | Insulin Glargine,hum.Rec.Anlog | 27 | suppressed |
| Triamterene-Hydrochlorothiazid | Triamterene/Hydrochlorothiazid | 27 | suppressed |
| Diltiazem 24hr Er (Cd) | Diltiazem Hcl | 26 | suppressed |
| Warfarin Sodium | Warfarin Sodium | 26 | suppressed |
| Colesevelam Hcl | Colesevelam Hcl | 25 | suppressed |
| Diazepam | Diazepam | 25 | suppressed |
| Olmesartan-Hydrochlorothiazide | Olmesartan/Hydrochlorothiazide | 25 | suppressed |
| Sotalol | Sotalol Hcl | 25 | suppressed |
| Cephalexin | Cephalexin | 24 | 22 |
| Fluticasone-Salmeterol | Fluticasone Propion/Salmeterol | 24 | suppressed |
| Prednisone | Prednisone | 24 | suppressed |
| Estradiol | Estradiol | 23 | suppressed |
| Lisinopril-Hydrochlorothiazide | Lisinopril/Hydrochlorothiazide | 23 | suppressed |
| Temazepam | Temazepam | 22 | suppressed |
| Enalapril Maleate | Enalapril Maleate | 21 | suppressed |
| Fenofibrate | Fenofibrate | 20 | suppressed |
| Irbesartan | Irbesartan | 20 | suppressed |
| Amoxicillin-Clavulanate Potass | Amoxicillin/Potassium Clav | 19 | 14 |
| Benazepril Hcl | Benazepril Hcl | 19 | suppressed |
| Latanoprost | Latanoprost | 19 | suppressed |
| Nano 2nd Gen Pen Needle | Pen Needle, Diabetic | 19 | suppressed |
| Shingrix | Varicella-Zoster Ge/As01b/Pf | 19 | 14 |
| Spironolactone | Spironolactone | 19 | suppressed |
| Trulicity | Dulaglutide | 19 | suppressed |
| Fluoxetine Hcl | Fluoxetine Hcl | 18 | suppressed |
| Ondansetron Hcl | Ondansetron Hcl | 18 | 15 |
| Paxlovid | Nirmatrelvir/Ritonavir | 18 | 18 |
| Pregabalin | Pregabalin | 18 | suppressed |
| Amlodipine Besylate-Benazepril | Amlodipine Besylate/Benazepril | 17 | suppressed |
| Azelastine Hcl | Azelastine Hcl | 17 | suppressed |
| Basaglar Kwikpen U-100 | Insulin Glargine,hum.Rec.Anlog | 17 | suppressed |
| Fluconazole | Fluconazole | 17 | 13 |
| Janumet | Sitagliptin Phos/Metformin Hcl | 17 | suppressed |
| Levetiracetam | Levetiracetam | 17 | suppressed |
| Mupirocin | Mupirocin | 17 | 16 |
| Megestrol Acetate | Megestrol Acetate | 16 | suppressed |
| Triazolam | Triazolam | 16 | suppressed |
| Xarelto | Rivaroxaban | 16 | suppressed |
| Clorazepate Dipotassium | Clorazepate Dipotassium | 15 | suppressed |
| Levocetirizine Dihydrochloride | Levocetirizine Dihydrochloride | 15 | suppressed |
| Quetiapine Fumarate | Quetiapine Fumarate | 15 | suppressed |
| Donepezil Hcl | Donepezil Hcl | 14 | suppressed |
| Levemir Flexpen | Insulin Detemir | 14 | suppressed |
| Oxybutynin Chloride | Oxybutynin Chloride | 14 | suppressed |
| Telmisartan | Telmisartan | 14 | suppressed |
| Acyclovir | Acyclovir | 13 | suppressed |
| Farxiga | Dapagliflozin Propanediol | 13 | suppressed |
| Nifedipine Er | Nifedipine | 13 | suppressed |
| Trimethoprim | Trimethoprim | 13 | suppressed |
| Ultra-Fine Mini Pen Needle | Pen Needle, Diabetic | 13 | suppressed |
| Bupropion Xl | Bupropion Hcl | 12 | suppressed |
| Doxycycline Hyclate | Doxycycline Hyclate | 12 | suppressed |
| Propranolol Hcl | Propranolol Hcl | 12 | suppressed |
| Valacyclovir | Valacyclovir Hcl | 12 | suppressed |
| Doxazosin Mesylate | Doxazosin Mesylate | 11 | suppressed |
| Esomeprazole Magnesium | Esomeprazole Magnesium | 11 | suppressed |
| Eszopiclone | Eszopiclone | 11 | suppressed |
| Fenofibric Acid | Fenofibric Acid (Choline) | 11 | suppressed |
| Ipratropium Bromide | Ipratropium Bromide | 11 | suppressed |
| Isosorbide Mononitrate Er | Isosorbide Mononitrate | 11 | suppressed |
| Novolin R Flexpen | Insulin Regular, Human | 11 | suppressed |
| Praluent Pen | Alirocumab | 11 | suppressed |
| Pulmicort Flexhaler | Budesonide | 11 | suppressed |
| Repatha Syringe | Evolocumab | 11 | suppressed |
| Tobramycin | Tobramycin | 11 | suppressed |
| Toujeo Max Solostar | Insulin Glargine,hum.Rec.Anlog | 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 | $429.06 · 23 records | Novo Nordisk Inc | ABRYSVO, COMIRNATY, FREESTYLE LIBRE 3, Fluad, Flucelvax, JARDIANCE, LEQVIO, MOUNJARO, OTEZLA, Ozempic, PREVNAR 20, REPATHA, Rybelsus, VOQUEZNA, VRAYLAR, Wegovy, ZEPBOUND | 8 | — |
| 2024 | — | — | — | — | Complete |
Questions to ask
Questions you could discuss with your doctor
- What role, if any, does Jardiance play in your treatment recommendations for me?
- How do you evaluate evidence when you have a financial relationship with ABBVIE INC.?
- 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 |
Full methodology · Questions & answers · Report a possible error