Denise Rivers, DO
Nephrology · Knoxville, TNNPI 1932193471
Payments from drug & device makers
What this record shows
Almost everything reported here is food and beverage — 98.3% of the total across 218 separate payments, which is the pattern of a clinician who attends manufacturer presentations rather than one with a consulting arrangement. It is spread thinly across 25 manufacturers, the largest accounting for just 14.2% — the pattern of someone who eats at a lot of different presentations. Reporting peaked in 2024 at $1,309 and has fallen 85.5% since, to $190 in 2025.
Across 218 payments — averaging $18.46 each. Meals, travel, consulting and speaking fees, gifts and royalties reported by drug and device makers.
- Amgen$573
- AstraZeneca$447
- Mallinckrodt Hospital Products Inc.$414
- Bayer$370
- Vifor Pharma, Inc.$363
- Otsuka America Pharmaceutical, Inc.$268
- plus $2K from 19 others
Across 80 payments — averaging $1876.89 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.
- Otsuka Pharmaceutical Development & Commercialization, Inc.$73K
- GSK$64K
- Baxter Healthcare$10K
- CSL Behring$3K
What the payments were for
- Food & beverage$3,95898%
- Education$662%
Most of this is food and beverage — typically meals provided during product presentations at a clinic or hospital. Nationally that is the single largest category of reported payments by count.
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 |
|---|---|---|
| Amgen(2 entities) | 29 | $573 |
| AstraZeneca(2 entities) | 24 | $447 |
| Mallinckrodt Hospital Products Inc. | 20 | $414 |
| Bayer | 24 | $370 |
| Vifor Pharma, Inc. | 16 | $363 |
| Otsuka America Pharmaceutical, Inc. | 17 | $268 |
| Travere Therapeutics, Inc. | 17 | $224 |
| Fresenius USA Marketing, Inc. | 11 | $186 |
| Calliditas Therapeutics US Inc. | 7 | $176 |
| Novartis | 8 | $143 |
| Aurinia Pharma U.S., Inc. | 9 | $143 |
| Daiichi Sankyo Inc. | 4 | $96 |
| ANI Pharmaceuticals, Inc. | 4 | $86 |
| Akebia Therapeutics Inc | 4 | $73 |
| OPKO Pharmaceuticals, LLC | 4 | $69 |
| Kyowa Kirin, Inc. | 4 | $67 |
| Alnylam Pharmaceuticals Inc. | 3 | $65 |
| GSK | 3 | $57 |
| Baxter Healthcare | 2 | $45 |
| Lundbeck LLC | 2 | $39 |
| Ardelyx, Inc. | 2 | $33 |
| Mallinckrodt Enterprises LLC | 1 | $28 |
| Rockwell Medical, Inc. | 1 | $24 |
| Lilly USA, LLC | 1 | $17 |
| Shire North American Group Inc | 1 | $17 |
How this compares
$4,024 in reported general payments places this provider in the 75th percentile of 229 nephrology providers in Tennessee.
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 |
|---|---|---|
| VeltassaPatiromer Calcium Sorbitex | 58 | $36,284 |
| ProcritEpoetin Alfa | 17 | $19,383 |
| Sevelamer Carbonate | 46 | $3,135 |
| Calcium Acetate | 57 | $2,202 |
| Potassium Chloride | 80 | $1,553 |
| Nitrofurantoin Mono-MacroNitrofurantoin Monohyd/M-Cryst | 52 | $1,045 |
| Chlorthalidone | 20 | $541 |
| Minoxidil | 17 | $515 |
| Bumetanide | 21 | $481 |
| Pantoprazole Sodium | 14 | $431 |
| Lisinopril | 70 | $372 |
| Olmesartan Medoxomil | 14 | $329 |
| Calcitriol | 18 | $290 |
| Tramadol Hcl | 13 | $208 |
| Atorvastatin Calcium | 25 | $197 |
Paid to pharmacies, not to this prescriber.
Other nephrology in Knoxville
- Ross NesbitKnoxville$452K
- Gerald BorrelliKnoxville$190K
- Jimmy GentryKnoxville$38K
- Ritu KhannaKnoxville$12K
- Urath SureshKnoxville$11K
- Kaitlin GreenKnoxville$6K
- Jamie DwyerNashville$461K
- Volker HaaseNashville$123K
- Chike NzerueCookeville$95K
- Talat IkizlerNashville$93K
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.