Healthcare provider profile · identity verified

Warren Hsiao, MD

Internal Medicine · HARBOR CITY, CA · NPI 1316095391

Profile state: partd only Open Payments: 2025 Medicare Part D: 2024 Last identity check: 2026-08-10 Page data build: 2026-08-12

Verified facts

What the public records show

We did not find matching Open Payments records for this doctor in 2025.

These records do not establish that a payment influenced prescribing or medical care.

Payment overview · 2025

General Payments

We did not find matching Open Payments records for this doctor in the selected program year.

Separate record types

Research & Ownership

Research Payments (direct recipient): not present in the loaded data

Associated Research Funding (for example, named PI): not present in the loaded data

Ownership / Investment: not present in the loaded data

These categories are never added into the General Payments headline. Associated research funding must not be described as money the doctor personally received unless the source record supports that conclusion.

Analysis 1 · Payment-linked products

Products named in Open Payments records

No payment-linked product analysis is available because no matching General Payment records were found for the selected year.

Public prescribing for products named in payments

There is no explicit payment-product set available for a Part D comparison.

The presence of the same drug in both datasets does not show that a payment caused or influenced a prescription.

Analysis 2 · Same-company prescribing overlap

Drugs reported in other payments from the same company that also appear in Medicare Part D

This analysis is independent from products named on this doctor’s individual payment records. A row appears only when the exact Open Payments reporting entity paid this doctor, that same reporting entity reported the drug or biological on at least 10 loaded General Payment records involving at least 2 distinct recipient NPIs, and this doctor has the same non-generic brand in public Part D data. This does not mean the company owns or manufactures the drug.

There is no payer-company set available for this comparison.

These facts do not show that a payment was for the drug, that the company owns or manufactures the drug, or that a payment caused or influenced prescribing.

Public Medicare Part D data

Provider-and-drug rows loaded for 2024

Brand	Generic	Claims	Beneficiaries
Atorvastatin Calcium	Atorvastatin Calcium	656	214
Rosuvastatin Calcium	Rosuvastatin Calcium	645	213
Amlodipine Besylate	Amlodipine Besylate	526	186
Losartan Potassium	Losartan Potassium	385	120
Lisinopril	Lisinopril	274	90
Levothyroxine Sodium	Levothyroxine Sodium	212	67
Atenolol	Atenolol	176	54
Metformin Hcl	Metformin Hcl	173	64
Allopurinol	Allopurinol	165	58
Jardiance	Empagliflozin	158	48
Metformin Hcl Er	Metformin Hcl	158	55
Omeprazole	Omeprazole	158	63
Ezetimibe	Ezetimibe	156	55
Potassium Chloride	Potassium Chloride	149	53
Meloxicam	Meloxicam	145	55
Gabapentin	Gabapentin	133	54
Metoprolol Tartrate	Metoprolol Tartrate	133	44
Tamsulosin Hcl	Tamsulosin Hcl	129	50
Lisinopril-Hydrochlorothiazide	Lisinopril/Hydrochlorothiazide	114	40
Glipizide	Glipizide	112	37
Alendronate Sodium	Alendronate Sodium	107	37
Furosemide	Furosemide	99	42
Finasteride	Finasteride	92	33
Pantoprazole Sodium	Pantoprazole Sodium	87	37
Pradaxa	Dabigatran Etexilate Mesylate	84	26
Spironolactone	Spironolactone	80	29
Triamcinolone Acetonide	Triamcinolone Acetonide	79	46
Bisoprolol Fumarate	Bisoprolol Fumarate	78	25
Simvastatin	Simvastatin	73	23
Nano 2nd Gen Pen Needle	Pen Needle, Diabetic	72	23
Trazodone Hcl	Trazodone Hcl	72	24
Abrysvo	Rsv Vacc, Pref A And Pref B/Pf	71	69
Clopidogrel	Clopidogrel Bisulfate	71	24
Humulin N Kwikpen	Insulin Nph Human Isophane	70	23
Terazosin Hcl	Terazosin Hcl	69	25
Cephalexin	Cephalexin	68	58
Hydrochlorothiazide	Hydrochlorothiazide	68	23
Prednisone	Prednisone	67	59
Albuterol Sulfate Hfa	Albuterol Sulfate	66	36
Lactulose	Lactulose	63	15
Hydrocortisone	Hydrocortisone	56	28
Terbinafine Hcl	Terbinafine Hcl	55	30
Fluoxetine Hcl	Fluoxetine Hcl	53	22
Repatha Sureclick	Evolocumab	52	suppressed
Adacel Tdap	Diph,pertuss(Acell),tet Vac/Pf	51	51
Duloxetine Hcl	Duloxetine Hcl	49	23
Fluticasone Propionate	Fluticasone Propionate	49	18
Azithromycin	Azithromycin	46	43
Warfarin Sodium	Warfarin Sodium	46	suppressed
Sertraline Hcl	Sertraline Hcl	40	13
Bupropion Xl	Bupropion Hcl	36	17
Hydralazine Hcl	Hydralazine Hcl	36	16
Chlorhexidine Gluconate	Chlorhexidine Gluconate	35	suppressed
Ozempic	Semaglutide	32	suppressed
Alvesco	Ciclesonide	31	suppressed
Carvedilol	Carvedilol	31	12
Colchicine	Colchicine	31	19
Nitrofurantoin Mono-Macro	Nitrofurantoin Monohyd/M-Cryst	31	31
Ibuprofen	Ibuprofen	29	17
Losartan-Hydrochlorothiazide	Losartan/Hydrochlorothiazide	28	suppressed
Mirtazapine	Mirtazapine	27	11
Mupirocin	Mupirocin	27	11
Ketoconazole	Ketoconazole	24	11
Doxycycline Monohydrate	Doxycycline Monohydrate	23	19
Wixela Inhub	Fluticasone Propion/Salmeterol	22	suppressed
Isosorbide Mononitrate Er	Isosorbide Mononitrate	21	suppressed
Acyclovir	Acyclovir	20	12
Ciprofloxacin Hcl	Ciprofloxacin Hcl	20	18
Azelastine Hcl	Azelastine Hcl	19	suppressed
Escitalopram Oxalate	Escitalopram Oxalate	17	suppressed
Metronidazole	Metronidazole	17	14
Propranolol Hcl	Propranolol Hcl	17	suppressed
Amoxicillin	Amoxicillin	16	15
Buspirone Hcl	Buspirone Hcl	16	suppressed
Eliquis	Apixaban	16	suppressed
Insulin Glargine-Yfgn	Insulin Glargine-Yfgn	15	suppressed
Pravastatin Sodium	Pravastatin Sodium	15	suppressed
Verapamil Er	Verapamil Hcl	15	suppressed
Digoxin	Digoxin	12	suppressed
Levetiracetam	Levetiracetam	12	suppressed
Liraglutide	Liraglutide	12	suppressed
Ofloxacin	Ofloxacin	12	11
Cholestyramine Light	Cholestyramine	11	suppressed
Clindamycin Phosphate	Clindamycin Phosphate	11	suppressed
Clonidine	Clonidine	11	suppressed
Erythromycin	Erythromycin Base	11	suppressed
Fluocinonide	Fluocinonide	11	suppressed
Shingrix	Varicella-Zoster Ge/As01b/Pf	11	11
Victoza 2-Pak	Liraglutide	11	suppressed
Xarelto	Rivaroxaban	11	suppressed

Timeline

Payment and prescribing data by year

Open Payments and Medicare Part D may refer to different years. They are shown separately rather than aligned as if they describe the same period.

Year	General Payments	Main payer	Explicit products	Company overlaps	Part D coverage
2025	—	—	—	—	—
2024	—	—	—	—	Complete

Questions to ask

Questions you could discuss with your doctor

Are there reasonable alternatives I should understand when we discuss treatment options?
How should I interpret the industry-payment records shown here in the context of my care?

These are general questions generated from reviewed templates. They are not personalized medical advice.

Sources and limitations

How to read this page

Payment and Medicare prescribing data can cover different years; every comparison shows both years explicitly.
Part D does not represent a doctor’s entire practice; it excludes many patients and is subject to CMS public-release thresholds.
Company–drug relationships must have an auditable source, a precise relationship type, and a valid evidence period. Unresolved mappings are not published.
Generic drug claims are not attributed to a specific manufacturer without manufacturer-level evidence.
When a source extract is incomplete, missing rows are never treated as proof of no payments or no prescriptions.

Loaded source releases

Dataset	Year	Publication	Source
CMS Open Payments — General Payments	2025	2026-06-30	Original source
Medicare Part D Prescribers by Provider and Drug	2024	2026-05-06	Original source
NPPES Data Dissemination V2	current / reference data	2026-08-10	Original source

Methodology version: 2.1

Editorial template version: 2.4

Product contract version: 2.0

Schema version: 0.7.0

Page data build: 2026-08-12T23:34:59.370714+00:00

Publication policy: eligible for indexing after public-launch controls are enabled

Full methodology · Questions & answers · Report a possible error