Alan Chang, MD
Gastroenterology · Doylestown, PANPI 1912992330
Payments from drug & device makers
What this record shows
Almost everything reported here is food and beverage — 99.4% of the total across 664 separate payments, which is the pattern of a clinician who attends manufacturer presentations rather than one with a consulting arrangement. It is spread thinly across 48 manufacturers, the largest accounting for just 21.3% — the pattern of someone who eats at a lot of different presentations. Reporting peaked in 2024 at $3,365 and has fallen 83.6% since, to $552 in 2025.
Across 664 payments — averaging $19.49 each. Meals, travel, consulting and speaking fees, gifts and royalties reported by drug and device makers.
- AbbVie$3K
- Salix Pharmaceuticals, A Division Of Bausch Health US, LLC$1K
- Takeda Pharmaceuticals U.S.A., Inc.$879
- Johnson & Johnson$836
- E.r. Squibb & Sons, L.L.C.$720
- Bristol Myers Squibb$562
- plus $6K from 42 others
Across 12 payments — averaging $3055.52 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.
- Intercept Pharmaceuticals, Inc.$34K
- Intercept Pharma Europe Ltd.$3K
What the payments were for
- Consulting fees$130%
- Food & beverage$12,86199%
- Education$701%
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.
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
$12,943 in reported general payments places this provider in the 85th percentile of 935 gastroenterology providers in Pennsylvania.
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 |
|---|---|---|
| StelaraUstekinumab | 21 | $597,938 |
| LinzessLinaclotide | 46 | $33,140 |
| XifaxanRifaximin | 12 | $29,116 |
| CreonLipase/Protease/Amylase | 11 | $28,389 |
| Mesalamine DrMesalamine | 17 | $17,344 |
| SutabSod Sulf/Pot Chloride/Mag Sulf | 99 | $15,806 |
| Mesalamine | 37 | $10,295 |
| Dexlansoprazole DrDexlansoprazole | 19 | $5,371 |
| Omeprazole | 342 | $2,845 |
| PlenvuPeg3350/Sod Sul/Nacl/Kcl/Asb/C | 15 | $2,077 |
| CholestyramineCholestyramine (With Sugar) | 26 | $1,782 |
| Budesonide DrBudesonide | 15 | $1,768 |
| Pantoprazole Sodium | 166 | $1,641 |
| Famotidine | 153 | $1,248 |
| Esomeprazole Magnesium | 35 | $1,109 |
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 |
|---|---|---|
| Johnson & JohnsonStelara | $836 | $597,93821 claims |
| AbbVieLinzess, Creon | $2,751 | $61,52957 claims |
| Salix Pharmaceuticals, A Division Of Bausch Health US, LLCXifaxan, Plenvu | $1,320 | $31,19327 claims |
| Braintree Laboratories, Inc.Sutab | $272 | $15,80699 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 935 gastroenterology providers in Pennsylvania.
Other gastroenterology in Doylestown
- Mayurathan KesavanDoylestown$167K
- Marion Anna ProtanoDoylestown$74K
- Miguel RegueiroPittsburgh$1.5M
- Adam PeytonAllentown$985K
- Shahin RahimianWaynesboro$592K
- Sandra El-HachemPittsburgh$472K
- Harshit KharaDanville$438K
- Kofi ClarkeHershey$426K
- Michael KochmanPhiladelphia$361K
- Gary LichtensteinPhiladelphia$342K
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.