Gregory Greenwood, MD
Nephrology · Winston-Salem, NCNPI 1316946858
Payments from drug & device makers
What this record shows
This record is dominated by speaking fees: $781,466 of the $946,590 with a category attached, or 82.6%. 41 manufacturers reported payments, led by AstraZeneca at 54.0% of the total. 2025 is the largest year on record at $225,635, 3.5 times the $65,351 reported in 2019. Among nephrology clinicians in NC with any reported payments, this total sits in the top 5% — high for the specialty, which is a reason to read the composition above rather than the number alone.
Across 1,895 payments — averaging $499.52 each. Meals, travel, consulting and speaking fees, gifts and royalties reported by drug and device makers.
- AstraZeneca$511K
- Otsuka America Pharmaceutical, Inc.$113K
- Boehringer Ingelheim$75K
- Lilly USA, LLC$74K
- Novo Nordisk$54K
- Bayer$50K
- plus $68K from 35 others
Across 836 payments — averaging $3716.44 each. Payments tied to a research study. These frequently flow through the physician to a hospital or research institution rather than to the physician personally.
- AstraZeneca$943K
- Boehringer Ingelheim Pharma GmbH & Co.kg$469K
- Amgen$423K
- Boehringer Ingelheim International GmbH$351K
- Novo Nordisk AS$258K
- Akebia Therapeutics Inc$237K
- plus $427K from 14 others
What the payments were for
- Consulting fees$38,0424%
- Speaking & faculty fees$781,46683%
- Travel & lodging$93,47110%
- Food & beverage$33,1644%
- Education$4480%
General payments by program year
Who reported the general payments
Companies are grouped under their corporate parent — a single manufacturer often files under several CMS reporting entities. Research and ownership payments are counted separately and are not in this table.
What the payments were tied to
Products named in the reported payments. Only payments of $100 or more are attributed here — the typical reported payment nationally is a meal worth about $16, and listing those product-by-product would be noise.
How this compares
$946,590 in reported general payments places this provider in the 95th percentile of 366 nephrology providers in North Carolina.
Medicare billing
What this is not: this is the amount Original Medicare Part B allowed for services this provider billed in 2024. It is not their income. It excludes Medicare Advantage — now more than half of all Medicare enrollment — along with Medicaid and all commercial insurance, and it is gross practice revenue before staff, rent, supplies and malpractice premiums. CMS also suppresses any figure covering ten or fewer patients, so low-volume providers appear smaller than they are.
Most prescribed under Part D
| Drug | Claims | Cost to plans & patients |
|---|---|---|
| FarxigaDapagliflozin Propanediol | 239 | $195,337 |
| JardianceEmpagliflozin | 240 | $183,016 |
| FilspariSparsentan | 12 | $135,060 |
| KerendiaFinerenone | 78 | $78,210 |
| VelphoroSucroferric Oxyhydroxide | 15 | $75,225 |
| LokelmaSodium Zirconium Cyclosilicate | 52 | $45,435 |
| XphozahTenapanor Hcl | 14 | $39,593 |
| AuryxiaFerric Citrate | 20 | $31,633 |
| Sevelamer Carbonate | 73 | $16,602 |
| JanuviaSitagliptin Phosphate | 24 | $14,510 |
| SpsSodium Polystyrene Sulfon/Sorb | 32 | $12,019 |
| DapagliflozinDapagliflozin Propanediol | 23 | $11,699 |
| EliquisApixaban | 13 | $7,358 |
| Valsartan | 147 | $3,074 |
| Potassium Citrate ErPotassium Citrate | 16 | $2,659 |
Paid to pharmacies, not to this prescriber.
Companies that both paid and supply prescribed drugs
These companies both reported payments to this provider and make drugs the provider prescribed under Medicare Part D in 2024. For most specialties this overlap is expected — a cardiologist who is paid by a cardiology drugmaker also treats heart disease. It is shown so the reader can see it, not because it implies anything on its own.
| Company | Paid to this provider | Part D cost of their drugs |
|---|---|---|
| AstraZenecaFarxiga, Lokelma | $511,304 | $240,772291 claims |
| Boehringer IngelheimJardiance | $75,235 | $183,016240 claims |
| Travere Therapeutics, Inc.Filspari | $29,185 | $135,06012 claims |
| BayerKerendia | $50,428 | $78,21078 claims |
| Fresenius USA Marketing, Inc.Velphoro | $209 | $75,22515 claims |
| Akebia Therapeutics IncAuryxia | $25,051 | $31,63320 claims |
| ANI Pharmaceuticals, Inc.Valsartan | $473 | $3,074147 claims |
Reading this fairly. The Part D column is what drug plans and patients paid pharmacies — this provider received none of it, and it reflects how many patients they treat and what those drugs cost. Against peers, this provider's reported payments sit in the 95th percentile of 366 nephrology providers in North Carolina.
Other nephrology in Winston-Salem
- Michael EtomiCharlotte$212K
- William KendrickGreenville$125K
- Jason EckelCary$123K
- Raven VooraSanford$111K
- Nam VoAsheville$89K
- Jennifer StoddardPinehurst$77K
- Barry FreedmanWinston Salem$67K
- James McCabeWilmington$56K
- Sammy MoghaziRaleigh$56K
- Matthew EllisDurham$51K
Where these figures come from
- Payments: CMS Open Payments, program years 2019–2025 (publication P06302026_06032026).
- Billing: Medicare Physician & Other Practitioners, data year 2024. Original Medicare Part B only.
- Identity: NPPES NPI Registry, July 2026.