William Lyday, MD
Gastroenterology · Roswell, GANPI 1134103195
Payments from drug & device makers
Across 16 payments — averaging $35.14 each. Meals, travel, consulting and speaking fees, gifts and royalties reported by drug and device makers.
- Phathom Pharmaceuticals, Inc.$139
- QOL Medical, LLC$115
- Apollo Endosurgery US Inc$114
- Pfizer$68
- Johnson & Johnson$39
- Cook Medical LLC$29
- plus $59 from 3 others
Across 1 payment — averaging $410.94 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.
- AbbVie$411
What the payments were for
- Grants$295%
- Food & beverage$53495%
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 |
|---|---|---|
| Phathom Pharmaceuticals, Inc. | 2 | $139 |
| QOL Medical, LLC | 5 | $115 |
| Apollo Endosurgery US Inc | 1 | $114 |
| Pfizer | 3 | $68 |
| Johnson & Johnson | 1 | $39 |
| Cook Medical LLC | 1 | $29 |
| Relievant Medsystems, Inc. | 1 | $24 |
| Medtronic | 1 | $19 |
| Nestle Healthcare Nutrition Inc. | 1 | $16 |
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.
- VOQUEZNA$125
How this compares
$562 in reported general payments places this provider in the 15th percentile of 492 gastroenterology providers in Georgia.
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 |
|---|---|---|
| Peg 3350-ElectrolyteSodium Chloride/Nahco3/Kcl/Peg | 49 | $904 |
| Pantoprazole Sodium | 44 | $466 |
| Omeprazole | 24 | $194 |
| Famotidine | 29 | $167 |
Paid to pharmacies, not to this prescriber.
Other gastroenterology in Roswell
- Meredith RiddickRoswell$752K
- Melvin BullockRoswell$283K
- Douglas WolfAtlanta$6.4M
- Aasim SheikhMarietta$6M
- Shahriar SedghiMacon$5.4M
- Jeffrey WilliamsAthens$2.5M
- Michael GalambosAtlanta$1.8M
- Nitin GuptaAtlanta$1.7M
- Bruce SalzbergSuwanee$1.4M
- Heba IskandarAtlanta$978K
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.