Nang Lok Tsang, MD
Internal Medicine · San Francisco, CANPI 1992873723
Payments from drug & device makers
What this record shows
Almost everything reported here is food and beverage — 99.9% of the total across 259 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 20 manufacturers, the largest accounting for just 17.3% — the pattern of someone who eats at a lot of different presentations. Reporting peaked in 2019 at $1,658 and has fallen 56.3% since, to $725 in 2025. Among internal medicine clinicians in CA with any reported payments, this total sits in the top 10% — high for the specialty, which is a reason to read the composition above rather than the number alone.
Across 259 payments — averaging $24.98 each. Meals, travel, consulting and speaking fees, gifts and royalties reported by drug and device makers.
- Novo Nordisk$1K
- AstraZeneca$886
- Lilly USA, LLC$708
- Johnson & Johnson$620
- GSK$480
- Boehringer Ingelheim$464
- plus $2K from 14 others
What the payments were for
- Food & beverage$6,463100%
- Education$70%
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 |
|---|---|---|
| Novo Nordisk | 54 | $1,117 |
| AstraZeneca | 29 | $886 |
| Lilly USA, LLC | 30 | $708 |
| Johnson & Johnson | 28 | $620 |
| GSK | 21 | $480 |
| Boehringer Ingelheim | 13 | $464 |
| Novartis | 18 | $412 |
| Bayer | 12 | $325 |
| AbbVie | 11 | $306 |
| ZOLL Services LLC (a/k/a ZOLL Lifecor Corp) | 5 | $302 |
| Merck | 13 | $261 |
| Pfizer | 6 | $150 |
| Amgen | 3 | $140 |
| E.r. Squibb & Sons, L.L.C. | 7 | $129 |
| Biogen | 2 | $42 |
| Kowa Pharmaceuticals America, Inc. | 2 | $41 |
| Astellas Pharma US Inc | 2 | $40 |
| Amarin Pharma, Inc. | 1 | $20 |
| Lexicon Pharmaceuticals, Inc. | 1 | $14 |
| Arbor Pharmaceuticals, 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.
How this compares
$6,470 in reported general payments places this provider in the 90th percentile of 13,581 internal medicine 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 |
|---|---|---|
| EliquisApixaban | 189 | $106,819 |
| JardianceEmpagliflozin | 121 | $91,593 |
| JanuviaSitagliptin Phosphate | 57 | $37,717 |
| EntrestoSacubitril/Valsartan | 35 | $19,742 |
| TradjentaLinagliptin | 54 | $14,216 |
| SantylCollagenase Clostridium Hist. | 24 | $13,266 |
| SymbicortBudesonide/Formoterol Fumarate | 39 | $7,927 |
| BreynaBudesonide/Formoterol Fumarate | 18 | $6,823 |
| Humalog Kwikpen U-100Insulin Lispro | 33 | $5,779 |
| Budesonide-Formoterol FumarateBudesonide/Formoterol Fumarate | 19 | $4,816 |
| Atorvastatin Calcium | 282 | $4,659 |
| Pantoprazole Sodium | 240 | $4,206 |
| Albuterol Sulfate HfaAlbuterol Sulfate | 88 | $3,543 |
| Lantus SolostarInsulin Glargine,hum.Rec.Anlog | 54 | $3,102 |
| Tamsulosin Hcl | 129 | $2,744 |
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 | $150 | $106,819189 claims |
| Boehringer IngelheimJardiance, Tradjenta | $464 | $105,809175 claims |
| MerckJanuvia | $261 | $37,71757 claims |
| NovartisEntresto | $412 | $19,74235 claims |
| AstraZenecaSymbicort | $886 | $7,92739 claims |
| Novo NordiskNovolog | $1,117 | $2,51630 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 90th percentile of 13,581 internal medicine providers in California.
Other internal medicine in San Francisco
- Fred CohenSan Francisco$929K
- John TeerlinkSan Francisco$819K
- Mark SmithSan Francisco$535K
- Lisa CapaldiniSan Francisco$434K
- Maria Dall'eraSan Francisco$417K
- Kenneth ColleySan Francisco$397K
- Louis CubbaSan Francisco$351K
- Daniel ButlerSan Francisco$347K
- Laurence CorashSan Francisco$336K
- Felicia StermanSan Francisco$298K
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.