Healthcare provider profile · identity verified

Derek Frank Williams, M.D.

Family Practice · HAWTHORNE, CA · NPI 1467405753

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

BrandGenericClaimsBeneficiaries
Atorvastatin CalciumAtorvastatin Calcium600190
Amlodipine BesylateAmlodipine Besylate347113
Losartan PotassiumLosartan Potassium18159
Metformin HclMetformin Hcl14748
LisinoprilLisinopril13547
Metoprolol SuccinateMetoprolol Succinate10933
HydrochlorothiazideHydrochlorothiazide9828
JanuviaSitagliptin Phosphate9023
Levothyroxine SodiumLevothyroxine Sodium8627
Metformin Hcl ErMetformin Hcl8530
Tamsulosin HclTamsulosin Hcl8331
CarvedilolCarvedilol6822
FurosemideFurosemide6826
FamotidineFamotidine6020
OmeprazoleOmeprazole5921
EliquisApixaban5816
Pantoprazole SodiumPantoprazole Sodium5720
Benazepril HclBenazepril Hcl5417
Albuterol Sulfate HfaAlbuterol Sulfate5318
OzempicSemaglutide52suppressed
Rosuvastatin CalciumRosuvastatin Calcium4920
Pioglitazone HclPioglitazone Hcl4619
GabapentinGabapentin4215
Clonidine HclClonidine Hcl4113
Lantus SolostarInsulin Glargine,hum.Rec.Anlog3911
Wixela InhubFluticasone Propion/Salmeterol39suppressed
Diclofenac SodiumDiclofenac Sodium3819
EzetimibeEzetimibe3812
Fluticasone PropionateFluticasone Propionate3620
Metoprolol TartrateMetoprolol Tartrate32suppressed
ClopidogrelClopidogrel Bisulfate29suppressed
Losartan-HydrochlorothiazideLosartan/Hydrochlorothiazide29suppressed
NaproxenNaproxen2917
Ondansetron OdtOndansetron29suppressed
Potassium ChloridePotassium Chloride2913
AllopurinolAllopurinol27suppressed
Escitalopram OxalateEscitalopram Oxalate27suppressed
TrulicityDulaglutide27suppressed
Donepezil HclDonepezil Hcl26suppressed
Nifedipine ErNifedipine26suppressed
Felodipine ErFelodipine23suppressed
Amlodipine Besylate-BenazeprilAmlodipine Besylate/Benazepril22suppressed
JardianceEmpagliflozin22suppressed
MeloxicamMeloxicam22suppressed
CiclopiroxCiclopirox21suppressed
FinasterideFinasteride2111
Hydralazine HclHydralazine Hcl20suppressed
KetoconazoleKetoconazole1915
Sertraline HclSertraline Hcl19suppressed
Alendronate SodiumAlendronate Sodium18suppressed
BreynaBudesonide/Formoterol Fumarate17suppressed
GlipizideGlipizide17suppressed
TradjentaLinagliptin17suppressed
Doxycycline HyclateDoxycycline Hyclate1612
SimvastatinSimvastatin16suppressed
ValsartanValsartan16suppressed
AtenololAtenolol15suppressed
Hydrocodone-AcetaminophenHydrocodone/Acetaminophen15suppressed
IbuprofenIbuprofen15suppressed
Lisinopril-HydrochlorothiazideLisinopril/Hydrochlorothiazide15suppressed
Triamterene-HydrochlorothiazidTriamterene/Hydrochlorothiazid15suppressed
Ultra-Fine Short Pen NeedlePen Needle, Diabetic15suppressed
Diltiazem 24hr Er (Cd)Diltiazem Hcl14suppressed
Tramadol HclTramadol Hcl14suppressed
Trazodone HclTrazodone Hcl14suppressed
Basaglar Kwikpen U-100Insulin Glargine,hum.Rec.Anlog13suppressed
ChlorthalidoneChlorthalidone13suppressed
IrbesartanIrbesartan13suppressed
Pravastatin SodiumPravastatin Sodium13suppressed
Amlodipine-ValsartanAmlodipine Besylate/Valsartan12suppressed
Benazepril-HydrochlorothiazideBenazepril/Hydrochlorothiazide12suppressed
Doxazosin MesylateDoxazosin Mesylate12suppressed
GemfibrozilGemfibrozil12suppressed
Omega-3 Acid Ethyl EstersOmega-3 Acid Ethyl Esters12suppressed
Verapamil SrVerapamil Hcl12suppressed
Glipizide ErGlipizide11suppressed
Levocetirizine DihydrochlorideLevocetirizine Dihydrochloride11suppressed
Trelegy ElliptaFluticasone/Umeclidin/Vilanter11suppressed

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.

YearGeneral PaymentsMain payerExplicit productsCompany overlapsPart D coverage
2025
2024 Complete

Questions to ask

Questions you could discuss with your doctor

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

Sources and limitations

How to read this page

Loaded source releases

DatasetYearPublicationSource
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