Douglas Linfert, MD
Nephrology · Wilmington, NCNPI 1710032255
Payments from drug & device makers
What this record shows
This record is dominated by consulting fees: $3,575 of the $4,539 with a category attached, or 78.8%. GSK accounts for 78.8% of it on its own, with 16 other manufacturers making up the rest. Reporting peaked in 2022 at $3,820 and has fallen 92.3% since, to $294 in 2025.
Across 41 payments — averaging $110.72 each. Meals, travel, consulting and speaking fees, gifts and royalties reported by drug and device makers.
- GSK$4K
- Fresenius USA Marketing, Inc.$171
- Galderma Laboratories, L.p.$145
- Otsuka America Pharmaceutical, Inc.$137
- AstraZeneca$107
- Baxter Healthcare$94
- plus $310 from 11 others
Across 139 payments — averaging $3401.83 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.
- GSK$250K
- Bayer$87K
- Akebia Therapeutics Inc$62K
- Otsuka Pharmaceutical Development & Commercialization, Inc.$54K
- Biogen$14K
- Novo Nordisk AS$6K
- plus $298 from 1 others
What the payments were for
- Consulting fees$3,57579%
- Food & beverage$96421%
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.
| Company | Payments | Total |
|---|---|---|
| GSK | 1 | $3,575 |
| Fresenius USA Marketing, Inc. | 9 | $171 |
| Galderma Laboratories, L.p. | 1 | $145 |
| Otsuka America Pharmaceutical, Inc. | 7 | $137 |
| AstraZeneca(2 entities) | 6 | $107 |
| Baxter Healthcare | 2 | $94 |
| Amgen | 3 | $56 |
| Sanofi | 1 | $40 |
| Calliditas Therapeutics US Inc. | 2 | $40 |
| Bayer | 2 | $36 |
| Mallinckrodt Hospital Products Inc. | 1 | $24 |
| Vifor Pharma, Inc. | 1 | $24 |
| Mallinckrodt Enterprises LLC | 1 | $21 |
| Boehringer Ingelheim | 1 | $20 |
| Shire North American Group Inc | 1 | $19 |
| Scpharmaceuticals Inc. | 1 | $19 |
| OPKO Pharmaceuticals, LLC | 1 | $13 |
How this compares
$4,539 in reported general payments places this provider in the 75th 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 |
|---|---|---|
| VelphoroSucroferric Oxyhydroxide | 23 | $79,322 |
| FarxigaDapagliflozin Propanediol | 40 | $28,844 |
| Cinacalcet Hcl | 45 | $11,897 |
| Sevelamer Carbonate | 53 | $7,998 |
| Calcium Acetate | 17 | $3,857 |
| Calcitriol | 62 | $1,120 |
| Nifedipine ErNifedipine | 37 | $888 |
| Carvedilol | 82 | $670 |
| Isosorbide Mononitrate ErIsosorbide Mononitrate | 29 | $662 |
| Allopurinol | 62 | $459 |
| Indapamide | 25 | $354 |
| Ramipril | 49 | $353 |
| Amlodipine Besylate | 23 | $133 |
| Tamsulosin Hcl | 18 | $93 |
| Candesartan Cilexetil | 13 | $71 |
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 |
|---|---|---|
| Fresenius USA Marketing, Inc.Velphoro | $171 | $79,32223 claims |
| AstraZenecaFarxiga | $107 | $28,84440 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 75th percentile of 366 nephrology providers in North Carolina.
Other nephrology in Wilmington
- James McCabeWilmington$56K
- Gregory GreenwoodWinston-Salem$947K
- Michael EtomiCharlotte$212K
- William KendrickGreenville$125K
- Jason EckelCary$123K
- Raven VooraSanford$111K
- Nam VoAsheville$89K
- Jennifer StoddardPinehurst$77K
- Barry FreedmanWinston Salem$67K
- Sammy MoghaziRaleigh$56K
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.