David Chamberlain, MD
Internal Medicine · Butte, MTNPI 1861423071
Payments from drug & device makers
What this record shows
Almost everything reported here is food and beverage — 99.3% of the total across 433 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 34 manufacturers, the largest accounting for just 20.7% — the pattern of someone who eats at a lot of different presentations. Among internal medicine clinicians in MT with any reported payments, this total sits in the top 5% — high for the specialty, which is a reason to read the composition above rather than the number alone.
Across 433 payments — averaging $17.96 each. Meals, travel, consulting and speaking fees, gifts and royalties reported by drug and device makers.
- AstraZeneca$2K
- Amgen$1K
- AbbVie$897
- Pfizer$820
- Lilly USA, LLC$645
- Novo Nordisk$551
- plus $2K from 28 others
What the payments were for
- Food & beverage$7,72299%
- Education$561%
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 |
|---|---|---|
| AstraZeneca | 60 | $1,606 |
| Amgen | 47 | $1,011 |
| AbbVie(2 entities) | 51 | $897 |
| Pfizer | 57 | $820 |
| Lilly USA, LLC | 50 | $645 |
| Novo Nordisk | 38 | $551 |
| Boehringer Ingelheim | 37 | $541 |
| Sanofi-aventis U.S. LLC | 14 | $270 |
| Novartis | 11 | $194 |
| GSK | 8 | $172 |
| Johnson & Johnson | 7 | $134 |
| Medtronic | 4 | $81 |
| Bayer | 5 | $77 |
| Dexcom, Inc. | 4 | $76 |
| Sanofi Pasteur Inc. | 4 | $71 |
| E.r. Squibb & Sons, L.L.C. | 4 | $67 |
| Exact Sciences | 3 | $66 |
| Regeneron Healthcare Solutions, Inc. | 4 | $66 |
| Biohaven Pharmaceutical Holding Company Ltd. | 3 | $53 |
| Abiomed | 2 | $41 |
| Xeris Pharmaceuticals, Inc. | 2 | $41 |
| Merck | 3 | $39 |
| Mylan Specialty L.p. | 2 | $36 |
| Lundbeck LLC | 2 | $34 |
| Corcept Therapeutics | 2 | $33 |
| Senseonics, Incorporated | 1 | $27 |
| Inspire Medical Systems, Inc. | 1 | $20 |
| Biohaven Pharmaceuticals, Inc. | 1 | $18 |
| ITI, Inc. (d/b/a Intra-cellular Therapies, Inc.) | 1 | $17 |
| Kyowa Kirin, Inc. | 1 | $16 |
| Abbott | 1 | $16 |
| Harmony Biosciences LLC | 1 | $14 |
| Astellas Pharma US Inc | 1 | $14 |
| Esperion Therapeutics, Inc. | 1 | $12 |
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
$7,778 in reported general payments places this provider in the 95th percentile of 244 internal medicine providers in Montana.
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 |
|---|---|---|
| EliquisApixaban | 95 | $117,045 |
| OzempicSemaglutide | 43 | $54,549 |
| JardianceEmpagliflozin | 35 | $48,770 |
| GlyxambiEmpagliflozin/Linagliptin | 36 | $39,940 |
| FarxigaDapagliflozin Propanediol | 24 | $37,567 |
| JanuviaSitagliptin Phosphate | 29 | $36,047 |
| XareltoRivaroxaban | 32 | $30,378 |
| MounjaroTirzepatide | 20 | $24,703 |
| Trelegy ElliptaFluticasone/Umeclidin/Vilanter | 29 | $19,460 |
| Breo ElliptaFluticasone/Vilanterol | 25 | $17,297 |
| Lantus SolostarInsulin Glargine,hum.Rec.Anlog | 87 | $14,853 |
| LinzessLinaclotide | 24 | $12,415 |
| Stiolto RespimatTiotropium Br/Olodaterol Hcl | 21 | $9,762 |
| Atorvastatin Calcium | 642 | $5,695 |
| Gabapentin | 317 | $5,311 |
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 |
|---|---|---|
| PfizerEliquis | $820 | $117,04595 claims |
| Boehringer IngelheimJardiance, Glyxambi, Stiolto Respimat | $541 | $98,47392 claims |
| Novo NordiskOzempic, Novolog | $551 | $56,98957 claims |
| AstraZenecaFarxiga | $1,606 | $37,56724 claims |
| GSKTrelegy Ellipta, Breo Ellipta | $172 | $36,75754 claims |
| MerckJanuvia | $39 | $36,04729 claims |
| Johnson & JohnsonXarelto | $134 | $30,37832 claims |
| Lilly USA, LLCMounjaro | $645 | $24,70320 claims |
| AbbVieLinzess | $897 | $12,41524 claims |
| Sanofi-aventis U.S. LLCLantus | $270 | $2,50719 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 95th percentile of 244 internal medicine providers in Montana.
Other internal medicine in Butte
- John PullmanButte$19K
- Joe GregoryButte$1K
- Paul SiddowayButte$374
- Florian CorteseButte$355
- Joseph PeilaBillings$148K
- Kari KaleBillings$83K
- Hayley MillerMissoula$67K
- Tracy RauschBillings$11K
- Brian HessBillings$8K
- Stacy KingslandGreat Falls$5K
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.