Dennis Riff, MD
Gastroenterology · Anaheim, CANPI 1922004662
Payments from drug & device makers
Across 667 payments — averaging $65.55 each. Meals, travel, consulting and speaking fees, gifts and royalties reported by drug and device makers.
- Phathom Pharmaceuticals, Inc.$18K
- Eli Lilly$11K
- Olympus America Inc.$3K
- AbbVie$3K
- Pfizer$3K
- Salix Pharmaceuticals, A Division Of Bausch Health US, LLC$2K
- plus $5K from 27 others
What the payments were for
- Speaking & faculty fees$15,05046%
- Travel & lodging$2,9109%
- Food & beverage$11,92536%
- Education$910%
- Other$2,7078%
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. | 42 | $17,851 |
| Eli Lilly | 2 | $11,043 |
| Olympus America Inc. | 1 | $2,707 |
| AbbVie | 161 | $2,612 |
| Pfizer | 53 | $2,596 |
| Salix Pharmaceuticals, A Division Of Bausch Health US, LLC | 138 | $2,103 |
| Ardelyx, Inc. | 47 | $976 |
| Gilead | 33 | $826 |
| Takeda Pharmaceuticals U.S.A., Inc. | 73 | $714 |
| Johnson & Johnson | 35 | $675 |
| Sanofi | 11 | $294 |
| Madrigal Pharmaceuticals | 17 | $259 |
| Lilly USA, LLC | 5 | $186 |
| Intercept Pharmaceuticals, Inc. | 7 | $134 |
| Redhill Biopharma Inc. | 6 | $108 |
| QOL Medical, LLC | 5 | $86 |
| Bristol Myers Squibb | 4 | $83 |
| Organon | 4 | $65 |
| Shionogi Inc | 3 | $55 |
| Vivus LLC | 2 | $43 |
| Ironwood Pharmaceuticals, Inc | 3 | $41 |
| Amgen | 2 | $37 |
| Braintree Laboratories, Inc. | 2 | $32 |
| Aimmune Therapeutics, Inc. | 2 | $27 |
| Biocon Biologics Inc | 1 | $27 |
| Intra-sana Laboratories | 1 | $22 |
| Ipsen Biopharmaceuticals, Inc | 1 | $21 |
| Nestle Healthcare Nutrition Inc. | 1 | $19 |
| Novo Nordisk | 1 | $18 |
| Ferring Pharmaceuticals Inc. | 1 | $18 |
| Exact Sciences | 1 | $16 |
| Celltrion USA Inc. | 1 | $14 |
| Shield Therapeutics Inc | 1 | $14 |
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$17,230
- EVIS X1 VIDEO SYSTEM CENTER$2,707
- PREVNAR - 13$1,411
- Skyrizi$372
- Epclusa$125
- Rinvoq$124
- OMVOH$121
- DUPIXENT$120
How this compares
$43,725 in reported general payments places this provider in the 85th percentile of 1,885 gastroenterology providers in California.
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 |
|---|---|---|
| Humira(Cf) PenAdalimumab | 19 | $271,146 |
| XifaxanRifaximin | 33 | $101,257 |
| LinzessLinaclotide | 95 | $69,944 |
| CreonLipase/Protease/Amylase | 24 | $63,077 |
| ZenpepLipase/Protease/Amylase | 16 | $52,364 |
| RezdiffraResmetirom | 11 | $47,959 |
| VemlidyTenofovir Alafenamide | 12 | $17,165 |
| Sod Sulf-Potass Sulf-Mag SulfSodium, Potassium,mag Sulfates | 259 | $16,117 |
| VoqueznaVonoprazan Fumarate | 11 | $15,035 |
| SutabSod Sulf/Pot Chloride/Mag Sulf | 78 | $12,473 |
| TrulancePlecanatide | 19 | $11,548 |
| Mesalamine | 27 | $8,756 |
| Pantoprazole Sodium | 322 | $4,585 |
| Omeprazole | 320 | $3,576 |
| PlenvuPeg3350/Sod Sul/Nacl/Kcl/Asb/C | 13 | $1,710 |
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 |
|---|---|---|
| AbbVieLinzess, Creon | $2,612 | $133,021119 claims |
| Salix Pharmaceuticals, A Division Of Bausch Health US, LLCXifaxan, Trulance, Plenvu | $2,103 | $114,51465 claims |
| Aimmune Therapeutics, Inc.Zenpep | $27 | $52,36416 claims |
| Madrigal PharmaceuticalsRezdiffra | $259 | $47,95911 claims |
| GileadVemlidy | $826 | $17,16512 claims |
| Phathom Pharmaceuticals, Inc.Voquezna | $17,851 | $15,03511 claims |
| Braintree Laboratories, Inc.Sutab, Suflave | $32 | $14,05491 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 1,885 gastroenterology providers in California.
Other gastroenterology in Anaheim
- Amit BhanvadiaAnaheim$1.7M
- Peter WinkleCypress$116.7M
- Manuchehr DaraniSanta Ana$17.7M
- Jatinder PruthiLancaster$4.4M
- Long DangWestminster$4.3M
- Muhammad SheikhFresno$4.3M
- Gregory WienerChula Vista$3.5M
- Gil MelmedLos Angeles$3M
- Christopher BowlusSacramento$3M
- Bennett RothLos Angeles$2.8M
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.