Theresa Toquyen Nguyen, DO
Child & Adolescent Psychiatry Physician · Tustin, CA
Theresa Toquyen Nguyen, DO is a child & adolescent psychiatry physician with a practice address in Tustin, California, and NPI 1679884928, issued on Jul 1, 2010. Check the license (California 20A12682, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Theresa Toquyen Nguyen
- Credential
- DO
- Primary taxonomy
- Child & Adolescent Psychiatry Physician 2084P0804X
- License numbers
- 20A12682 CA
007228 AZ
Self-reported in NPPES; status is on the state search - Practice location
- 15405 Lansdowne RD, Tustin, CA 92782
- Phone
- (925) 997-9093
- Enumerated
- Jul 1, 2010
- Record last updated
- Jun 28, 2023
- Medicare enrollment
- Enrolled (PECOS I20191212002388); accepts Medicare assignment
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest child & adolescent psychiatry physician records → All 1,009 in California → Look up another NPI →
Also registered at 15405 Lansdowne RD
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Charlene Nguon-Rodriguez, AMFT, APCCMarriage & Family Therapist1598322075
- Mark PompeoCounselor1770132516
- Elizabeth SalasAddiction (Substance Use Disorder) Counselor1821713660
- Shawn Sinclair, LCSWClinical Social Worker1174167373
Verify Theresa Toquyen Nguyen in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license 20A12682Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Bills Medicare through one group practice
- County OF ModocAlturas, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Theresa Toquyen Nguyen among 1,009 child & adolescent psychiatry physician records in California
Theresa Toquyen Nguyen, DO is one of 1,009 child & adolescent psychiatry physician records with a practice address in California. 55% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2010, is newer than 69% of them.
- NPI issued2010 · 69% of these records are older, 26% newer
- In a Medicare fileYes · 55% of these records are
- In the CMS Doctors and Clinicians fileYes · 21% of these records are
- Graduated2010 · median 2005 among the 215 with a school on file
- Record last updated2023 · 57% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 2084P0804X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Child & Adolescent Psychiatry Physician providers in California
There are 1,009 child & adolescent psychiatry physician records in California.
All 1,009 in California → Every provider in Tustin → Child & Adolescent Psychiatry Physician nationwide →
The 8 child & adolescent psychiatry physician records with the nearest ZIP codes
- Behrouz Namdari, M.D.Anaheim, CA 928011972829711
- Sabena Panhwar, MDAnaheim, CA 928011639339997
- Jose Gamboa, MDAnaheim, CA 928051275615718
- David Allyn, MDAnaheim, CA 928071952472987
- Patricia Cahill, MDAnaheim, CA 928071427129451
- Alex Garcia, MDAnaheim, CA 928071487721494
- Jyotsna Thakkar, MDAnaheim, CA 928071962573865
- Saeed Eshraghi, M.D.Anaheim, CA 928081073740254
Common questions
What is Theresa Toquyen Nguyen, DO's NPI number?
Theresa Toquyen Nguyen, DO's National Provider Identifier (NPI) is 1679884928, issued on Jul 1, 2010. An NPI identifies a provider in billing; it is not a license.
Where is Theresa Toquyen Nguyen, DO located?
The NPPES record lists a practice address at 15405 Lansdowne RD, Tustin, CA, 92782. Phone: (925) 997-9093. Providers update this record themselves, so call before visiting.
How can I verify Theresa Toquyen Nguyen, DO's license?
NPPES lists California license number 20A12682, 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.
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.