Marc Demyun, MD
Internal Medicine · Greenville, TXNPI 1952366684
Payments from drug & device makers
Across 89 payments — averaging $252.21 each. Meals, travel, consulting and speaking fees, gifts and royalties reported by drug and device makers.
- Cleerly, Inc.$15K
- Gilead$6K
- Novartis$522
- Pfizer$325
- Johnson & Johnson$323
- Medtronic$141
- plus $466 from 10 others
What the payments were for
- Consulting fees$4,20055%
- Speaking & faculty fees$401%
- Travel & lodging$1,03614%
- Food & beverage$2,34131%
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 |
|---|---|---|
| Cleerly, Inc. | 2 | $14,830 |
| Gilead | 14 | $5,840 |
| Novartis | 7 | $522 |
| Pfizer | 15 | $325 |
| Johnson & Johnson | 18 | $323 |
| Medtronic(2 entities) | 7 | $141 |
| Salix Pharmaceuticals, A Division Of Bausch Health US, LLC | 8 | $134 |
| AstraZeneca | 5 | $96 |
| Mylan Specialty L.p. | 4 | $61 |
| Biofire Diagnostics, LLC | 1 | $40 |
| E.r. Squibb & Sons, L.L.C. | 2 | $33 |
| Fisher & Paykel Healthcare Inc | 1 | $25 |
| Merck | 2 | $24 |
| Abbott | 1 | $23 |
| Solventum Corporation | 1 | $19 |
| Biomerieux Inc | 1 | $13 |
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.
- Veklury$5,497
How this compares
$22,447 in reported general payments places this provider in the 95th percentile of 7,675 internal medicine providers in Texas.
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 |
|---|---|---|
| Montelukast Sodium | 14 | $151 |
| Levothyroxine Sodium | 18 | $126 |
| Doxycycline Hyclate | 13 | $125 |
| Atorvastatin Calcium | 17 | $115 |
| Donepezil Hcl | 13 | $99 |
| Trazodone Hcl | 11 | $72 |
| Amlodipine Besylate | 13 | $44 |
| Pantoprazole Sodium | 12 | $34 |
Paid to pharmacies, not to this prescriber.
Other internal medicine in Greenville
- Jan BurgerHouston$47.3M
- Nitin JainHouston$33.2M
- Muhammad IrfanTomball$30.6M
- Aung NaingHouston$30.6M
- Robert BassSan Antonio$25.6M
- Preetesh JainHouston$19.5M
- Paolo StratiHouston$19.2M
- Hernan SalazarSan Antonio$18.5M
- Nicholas ShortHouston$17.6M
- Salma SaigerMesquite$16.1M
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.