Ghassan Alzayer, MD
Gastroenterology · Washington, DCNPI 1396144804
Payments from drug & device makers
What this record shows
Almost everything reported here is food and beverage — 92.5% of the total across 23 separate payments, which is the pattern of a clinician who attends manufacturer presentations rather than one with a consulting arrangement. 7 manufacturers reported payments, led by Gilead at 32.3% of the total. Reporting peaked in 2019 at $755 and has fallen 83.5% since, to $124 in 2025. That places this record below the midpoint for gastroenterology clinicians in DC, where the typical reported total is $1,183.
Across 23 payments — averaging $67.31 each. Meals, travel, consulting and speaking fees, gifts and royalties reported by drug and device makers.
- Gilead$500
- AbbVie$473
- Pfizer$244
- Johnson & Johnson$176
- Boston Scientific$69
- Pentax Of America, Inc.$67
- plus $19 from 1 others
What the payments were for
- Food & beverage$1,43293%
- Education$1167%
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 |
|---|---|---|
| Gilead | 5 | $500 |
| AbbVie | 6 | $473 |
| Pfizer | 3 | $244 |
| Johnson & Johnson | 5 | $176 |
| Boston Scientific | 2 | $69 |
| Pentax Of America, Inc. | 1 | $67 |
| Takeda Pharmaceuticals U.S.A., Inc. | 1 | $19 |
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
$1,548 in reported general payments places this provider in the 50th percentile of 77 gastroenterology providers in District of Columbia.
See all gastroenterology providers in District of Columbia →
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 |
|---|---|---|
| Omeprazole | 121 | $3,395 |
| Gavilyte-GPeg3350/Sod Sulf,bicarb,cl/Kcl | 74 | $1,048 |
| Sod Sulf-Potass Sulf-Mag SulfSodium, Potassium,mag Sulfates | 17 | $962 |
| Lansoprazole | 12 | $873 |
| Pantoprazole Sodium | 58 | $790 |
| Peg-3350 And ElectrolytesPeg3350/Sod Sulf,bicarb,cl/Kcl | 29 | $564 |
| Metronidazole | 12 | $141 |
Paid to pharmacies, not to this prescriber.
Other gastroenterology in Washington
- James LewisWashington$1M
- John HoganWashington$354K
- Mark MattarWashington$349K
- Jessica KormanWashington$171K
- Mitesh PatelWashington$90K
- Sumona BhattacharyaWashington$87K
- Roshan BashirWashington$40K
- Bruce LuxonWashington$37K
- Lauren GeorgeWashington$32K
- Dominique HowardWashington$29K
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.