NPPES file of Aug 9, 2026

Theresa Thu Thao Nguyen, D.O.

Ophthalmology Physician · Redwood City, CA

Theresa Thu Thao Nguyen, D.O. is an ophthalmology physician with a practice address in Redwood City, California, and NPI 1427206093, issued on Sep 8, 2008. Check the license on the Medical Board of California; the Medicare figures below come from public CMS files.

Record from CMS NPPES, file of Aug 9, 2026 · Medicare files 2024 · method · Verify with CMS →

NPPES recordNPPES file of Aug 9, 2026
1427206093
Name
Theresa Thu Thao Nguyen
Credential
D.O.
Primary taxonomy
Ophthalmology Physician 207W00000X
License numbers
DO034365 DC
125051600 IL
H0073311 MD
256836-1 NY
0102202992 VA
Self-reported in NPPES; status is on the state search
Practice location
905 Maple St, Redwood City, CA 94063
Phone
(650) 299-2066
Enumerated
Sep 8, 2008
Record last updated
Aug 14, 2024
Medicare enrollment
Enrolled (PECOS I20150916000634); accepts Medicare assignment
Entity
Type 1 · individual
Public record from CMS NPPES (open it on the CMS NPI Registry). Enrollment, assignment, school and telehealth: CMS Doctors and Clinicians file, Aug 2026. A record is not a license: verify it with the state board.
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Also registered at 905 Maple St

A shared address usually means a shared clinic or building; it does not show who employs whom.

  1. Sarah BartyRegistered Nurse1306721618
  2. Donald Chan, MDDiagnostic Radiology Physician1235768268
  3. Megan Demots, DPTPhysical Therapist1831086800
  4. Shawna McCarthyCertified Respiratory Therapist1265367940
  5. William Wang, MDStudent in an Organized Health Care Education/Training Program1669913984

Verify Theresa Thu Thao Nguyen in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersMedical Board of CaliforniaCheck the board
  3. 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
  4. 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
  5. 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Open the California license search

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17% fewer Medicare Part D claims than the average ophthalmology physician in 2024

1,259 Medicare Part D claims for 307 beneficiaries, against an average of 1,518 among the 16,459 providers of this specialty who prescribed in Part D. Brand-name drugs were 29% of claims. 13 claims were for opioids.

  1. Theresa Nguyen1,259
  2. Specialty average1,518

Most prescribed

  1. Prednisolone Acetate210 claims
  2. Latanoprost200 claims
  3. Polymyxin B Sul-Trimethoprim120 claims
  4. Fluorometholone107 claims
  5. Timolol Maleate105 claims
  6. Cyclosporine76 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: $149.43

1 payment: food and beverage; the largest payer was Alcon Vision LLC. The 13,221 providers of this specialty with any payment received $4,535.02 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.

  1. Theresa Nguyen$149.43
  2. Specialty average$4,535.02

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

  1. Permanente Medical Group IncRedwood City, CA

Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).

Theresa Thu Thao Nguyen among 2,899 ophthalmology physician records in California

Theresa Thu Thao Nguyen, D.O. is one of 2,899 ophthalmology physician records with a practice address in California. 79% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2008, is newer than 67% of them.

  • NPI issued2008 · 67% of these records are older, 28% newer
  • In a Medicare fileYes · 79% of these records are
  • In the CMS Doctors and Clinicians fileYes · 66% of these records are
  • Graduated2006 · median 2001 among the 1,907 with a school on file
  • Record last updated2024 · 67% of these records were not updated in five years or more

Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207W00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).

Ophthalmology Physician providers in California

There are 2,899 ophthalmology physician records in California.

The 8 ophthalmology physician records with the nearest ZIP codes

  1. William Chang, MDRedwood City, CA 940631487732020
  2. Paul Chen, MDRedwood City, CA 940631184798464
  3. Ronald Melles, MDRedwood City, CA 940631104904747
  4. Henry Upton, M.D.Redwood City, CA 940631285732669
  5. Judith Nevitt, M.D.Redwood City, CA 940611194816058
  6. James Tearse, MDRedwood City, CA 940611811099435
  7. James Abrams, M.D.San Bruno, CA 940661912903329
  8. Richard Braunstein, M.D.San Carlos, CA 940701639104433

Common questions

What is Theresa Thu Thao Nguyen, D.O.'s NPI number?

Theresa Thu Thao Nguyen, D.O.'s National Provider Identifier (NPI) is 1427206093, issued on Sep 8, 2008. An NPI identifies a provider in billing; it is not a license.

Where is Theresa Thu Thao Nguyen, D.O. located?

The NPPES record lists a practice address at 905 Maple St, Redwood City, CA, 94063. Phone: (650) 299-2066. Providers update this record themselves, so call before visiting.

How can I verify Theresa Thu Thao Nguyen, D.O.'s license?

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 Theresa Thu Thao Nguyen, D.O. prescribe under Medicare Part D?

In 2024, Theresa Thu Thao Nguyen, D.O. had 1,259 Medicare Part D claims for 307 beneficiaries; the average among ophthalmology physician prescribers was 1,518. 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.