David Irizarry, MD
Endocrinology, Diabetes & Metabolism · Knoxville, TNNPI 1518282839
Payments from drug & device makers
What this record shows
This record is dominated by speaking fees: $81,381 of the $96,105 with a category attached, or 84.7%. Novo Nordisk accounts for 91.2% of it on its own, with 49 other manufacturers making up the rest. Reporting peaked in 2022 at $39,271 and has fallen 52.3% since, to $18,722 in 2025.
Across 549 payments — averaging $175.05 each. Meals, travel, consulting and speaking fees, gifts and royalties reported by drug and device makers.
- Novo Nordisk$88K
- Intuitive Surgical$1K
- Lilly USA, LLC$1K
- Amgen$1K
- Dexcom, Inc.$611
- Sanofi-aventis U.S. LLC$483
- plus $4K from 44 others
What the payments were for
- Speaking & faculty fees$81,38185%
- Travel & lodging$4,8665%
- Food & beverage$9,21010%
- Education$6471%
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
$96,105 in reported general payments places this provider in the 85th percentile of 130 endocrinology, diabetes & metabolism providers in Tennessee.
See all endocrinology, diabetes & metabolism 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 |
|---|---|---|
| OzempicSemaglutide | 95 | $141,215 |
| MounjaroTirzepatide | 44 | $72,988 |
| Omnipod 5 Dexg7g6 Pods (Gen 5)Insulin Pump Cart,auto,bt,g6/7 | 39 | $45,808 |
| Soliqua 100-33Insulin Glargine/Lixisenatide | 31 | $42,090 |
| Synjardy XrEmpagliflozin/Metformin Hcl | 24 | $40,924 |
| Evenity (2 Syringes)Romosozumab-Aqqg | 15 | $36,182 |
| TymlosAbaloparatide | 13 | $33,830 |
| JardianceEmpagliflozin | 29 | $32,090 |
| Tresiba Flextouch U-200Insulin Degludec | 11 | $30,862 |
| RybelsusSemaglutide | 13 | $25,004 |
| Tresiba Flextouch U-100Insulin Degludec | 25 | $19,741 |
| LyumjevInsulin Lispro-Aabc | 11 | $9,759 |
| TirosintLevothyroxine Sodium | 22 | $7,932 |
| NovologInsulin Aspart | 18 | $7,744 |
| Omnipod 5 Dexg7g6 Intro(Gen 5)Insulin Pmp Cart,aut,g6/7,cntr | 12 | $6,701 |
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 |
|---|---|---|
| Novo NordiskOzempic, Rybelsus, Novolog | $87,658 | $173,964126 claims |
| Lilly USA, LLCMounjaro, Lyumjev | $1,016 | $82,74755 claims |
| Boehringer IngelheimSynjardy Xr, Jardiance | $126 | $73,01353 claims |
| Sanofi-aventis U.S. LLCSoliqua 100-33 | $483 | $42,09031 claims |
| AmgenEvenity (2 Syringes) | $1,015 | $36,18215 claims |
| Radius Health, Inc.Tymlos | $219 | $33,83013 claims |
| IBSA Pharma Inc.Tirosint | $126 | $7,93222 claims |
| Amneal Pharmaceuticals LLCLevothyroxine Sodium, Unithroid | $79 | $6,668442 claims |
| AbbVieSynthroid | $109 | $5,72550 claims |
| PfizerLevoxyl | $13 | $54811 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 85th percentile of 130 endocrinology, diabetes & metabolism providers in Tennessee.
Other endocrinology, diabetes & metabolism in Knoxville
- Amit VoraKnoxville$579K
- Casey PageKnoxville$82K
- Mubashir MahmoodKnoxville$26K
- Thomas DotyKnoxville$21K
- Daniel McCammonKnoxville$9K
- Peter CampbellKnoxville$5K
- Gregory MoffittKnoxville$5K
- Robert GeierKnoxville$4K
- Alan CohenMemphis$1.4M
- Craig WierumNashville$1.3M
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.