Derick L. Ly, D.O., M.S.
Psychiatry Physician · Ontario, CA
Derick L. Ly, D.O., M.S. is a psychiatry physician with a practice address in Ontario, California, and NPI 1962744417, issued on Mar 22, 2013. Check the license (California 13326, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Derick L. Ly
- Credential
- D.O., M.S.
- Primary taxonomy
- Psychiatry Physician 2084P0800X
- License number
- 13326 CA
Self-reported in NPPES; status is on the state search - Practice location
- 2940 Inland Empire Blvd, Ontario, CA 91764
- Phone
- (909) 458-1350
- Enumerated
- Mar 22, 2013
- Record last updated
- Mar 31, 2025
- Medicare enrollment
- Enrolled (PECOS I20161104001996); accepts Medicare assignment
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest psychiatry physician records → All 8,673 in California → Look up another NPI →
Also registered at 2940 Inland Empire Blvd
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Mary AdetulaRegistered Nurse1437658929
- Gal Andres, MDPsychiatry Physician1043779903
- Pamela Apostolou, REGISTERED NURSEPsychiatric/Mental Health Registered Nurse1982176475
- Toni ArmstrongMental Health Counselor1194112300
- Maria ArroyoCounselor1386012151
- Jesus Avitia, CADC IIAddiction (Substance Use Disorder) Counselor1780159954
Verify Derick L. Ly in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license 13326Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
2% more Medicare Part D claims than the average psychiatry physician in 2024
1,018 Medicare Part D claims for 74 beneficiaries, against an average of 1,000 among the 35,054 providers of this specialty who prescribed in Part D. Brand-name drugs were 5% of claims.
Most prescribed
- Trazodone Hcl84 claims
- Benztropine Mesylate67 claims
- Aripiprazole65 claims
- Sertraline Hcl64 claims
- Quetiapine Fumarate52 claims
- Bupropion Xl44 claims
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
Industry payments in 2024: $194.92
6 payments; by number, the most common kind was food and beverage; the largest payer was Teva Pharmaceuticals USA, Inc. The 13,693 providers of this specialty with any payment received $4,954.93 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
Bills Medicare through one group practice
- County OF San BernardinoSan Bernardino, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Derick L. Ly among 8,673 psychiatry physician records in California
Derick L. Ly, D.O., M.S. is one of 8,673 psychiatry physician records with a practice address in California. 67% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2013, is newer than 69% of them.
- NPI issued2013 · 69% of these records are older, 29% newer
- In a Medicare fileYes · 67% of these records are
- In the CMS Doctors and Clinicians fileYes · 38% of these records are
- Graduated2012 · median 2005 among the 3,295 with a school on file
- Record last updated2025 · 54% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 2084P0800X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Psychiatry Physician providers in California
There are 8,673 psychiatry physician records in California.
All 8,673 in California → Every provider in Ontario → Psychiatry Physician nationwide →
The 8 psychiatry physician records with the nearest ZIP codes
- Gal Andres, MDOntario, CA 917641043779903
- Jacquelyn Dang, D.O.Ontario, CA 917641154778934
- Amit Kapoor, MDOntario, CA 917641194467274
- Usha Sachdev, M.D.Ontario, CA 917641508085465
- David Takehana, DOOntario, CA 917641518548221
- Pooja Amin, MDMontclair, CA 917631568081982
- Paul Brown, M.D.Diamond Bar, CA 917651437361789
- Amanda Degan, DOMontclair, CA 917631629501770
Common questions
What is Derick L. Ly, D.O., M.S.'s NPI number?
Derick L. Ly, D.O., M.S.'s National Provider Identifier (NPI) is 1962744417, issued on Mar 22, 2013. An NPI identifies a provider in billing; it is not a license.
Where is Derick L. Ly, D.O., M.S. located?
The NPPES record lists a practice address at 2940 Inland Empire Blvd, Ontario, CA, 91764. Phone: (909) 458-1350. Providers update this record themselves, so call before visiting.
How can I verify Derick L. Ly, D.O., M.S.'s license?
NPPES lists California license number 13326, as entered by the provider. Search the Medical Board of California at https://www.mbc.ca.gov/License-Verification/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Derick L. Ly, D.O., M.S. prescribe under Medicare Part D?
In 2024, Derick L. Ly, D.O., M.S. had 1,018 Medicare Part D claims for 74 beneficiaries; the average among psychiatry physician prescribers was 1,000. Part D covers Medicare prescriptions only.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.