William Chastant, MD
Gastroenterology · Lafayette, LANPI 1770087504
Payments from drug & device makers
Across 148 payments — averaging $22.77 each. Meals, travel, consulting and speaking fees, gifts and royalties reported by drug and device makers.
- AbbVie$1K
- Takeda Pharmaceuticals U.S.A., Inc.$451
- Johnson & Johnson$347
- Phathom Pharmaceuticals, Inc.$261
- Ardelyx, Inc.$182
- Salix Pharmaceuticals, A Division Of Bausch Health US, LLC$178
- plus $659 from 13 others
What the payments were for
- Food & beverage$3,31098%
- Education$602%
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 |
|---|---|---|
| AbbVie | 48 | $1,293 |
| Takeda Pharmaceuticals U.S.A., Inc. | 25 | $451 |
| Johnson & Johnson(2 entities) | 12 | $347 |
| Phathom Pharmaceuticals, Inc. | 15 | $261 |
| Ardelyx, Inc. | 10 | $182 |
| Salix Pharmaceuticals, A Division Of Bausch Health US, LLC | 9 | $178 |
| Bristol Myers Squibb | 5 | $114 |
| Sanofi | 1 | $111 |
| Pfizer | 5 | $106 |
| Intercept Pharmaceuticals, Inc. | 4 | $62 |
| Ipsen Biopharmaceuticals, Inc | 2 | $43 |
| Aimmune Therapeutics, Inc. | 2 | $40 |
| AstraZeneca | 2 | $39 |
| QOL Medical, LLC | 2 | $36 |
| Ironwood Pharmaceuticals, Inc | 2 | $31 |
| Cook Medical LLC | 1 | $23 |
| Braintree Laboratories, Inc. | 1 | $22 |
| Madrigal Pharmaceuticals | 1 | $16 |
| Celltrion USA Inc. | 1 | $15 |
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
$3,370 in reported general payments places this provider in the 45th percentile of 254 gastroenterology providers in Louisiana.
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 |
|---|---|---|
| Sod Sulf-Potass Sulf-Mag SulfSodium, Potassium,mag Sulfates | 27 | $1,610 |
| Pantoprazole Sodium | 37 | $283 |
| Dicyclomine Hcl | 12 | $120 |
Paid to pharmacies, not to this prescriber.
Other gastroenterology in Lafayette
- Jacob BreauxLafayette$407K
- Eric TrawickLafayette$209K
- Jacob KarrLafayette$182K
- Jacque NoelLafayette$88K
- Stephen AbshireLafayette$53K
- Erick SalvatierraLafayette$27K
- Humberto AguilarShreveport$13.1M
- Gary ReissMarrero$10M
- Bal BhandariBastrop$6.4M
- Gregory GaspardBaton Rouge$4M
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.