NPPES file of Aug 9, 2026

Sylvester Nguyen

Optometrist · Modesto, CA

Sylvester Nguyen is an optometrist with a practice address in Modesto, California, and NPI 1861844680, issued on Jul 5, 2016. Check the license (California 33381, as entered in NPPES) with the California board that licenses this profession; 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
1861844680
Name
Sylvester Nguyen
Primary taxonomy
Optometrist 152W00000X
License numbers
33381 CA
CA298165 CA
Self-reported in NPPES; status is on the state search
Practice location
3200 Sisk RD, Modesto, CA 95356
Phone
(510) 332-3175
Enumerated
Jul 5, 2016
Record last updated
Feb 12, 2021 (not updated in 5 years: call before relying on the address or phone)
Medicare enrollment
Enrolled (PECOS I20161024000728); 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 3200 Sisk RD

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

  1. Lina Lee, O.D.Optometrist1215186598

Verify Sylvester Nguyen in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersWhich California board licenses this profession
    Search for license 33381
    Check 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
Find the California license search

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87% fewer Medicare Part D claims than the average optometrist in 2024

35 Medicare Part D claims for 18 beneficiaries, against an average of 277 among the 33,128 providers of this specialty who prescribed in Part D. Brand-name drugs were 74% of claims.

  1. Sylvester Nguyen35
  2. Specialty average277

Most prescribed

  1. Cyclosporine24 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.

Bills Medicare through one group practice

  1. Permanente Medical Group IncSacramento, CA

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

Sylvester Nguyen among 8,308 optometrist records in California

Sylvester Nguyen is one of 8,308 optometrist 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 2016, is newer than 73% of them.

  • NPI issued2016 · 73% of these records are older, 24% newer
  • In a Medicare fileYes · 67% of these records are
  • In the CMS Doctors and Clinicians fileYes · 43% of these records are
  • Graduated2016 · median 2008 among the 3,573 with a school on file
  • Record last updated2021 · 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 152W00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).

Optometrist providers in California

There are 8,308 optometrist records in California.

The 8 optometrist records with the nearest ZIP codes

  1. Angela Abe, OPTModesto, CA 953561336108885
  2. Chea-Yo Chang, O.D.Modesto, CA 953561811192289
  3. Jack Hall, O.D.Modesto, CA 953561639228331
  4. Lina Lee, O.D.Modesto, CA 953561215186598
  5. Patrick Lonowski, O.D.Modesto, CA 953561073520425
  6. Daniel Lundgren, ODModesto, CA 953561811986375
  7. Diana MehannyModesto, CA 953561215636279
  8. Lincoln Service, O.D.Modesto, CA 953561619028842

Common questions

What is Sylvester Nguyen's NPI number?

Sylvester Nguyen's National Provider Identifier (NPI) is 1861844680, issued on Jul 5, 2016. An NPI identifies a provider in billing; it is not a license.

Where is Sylvester Nguyen located?

The NPPES record lists a practice address at 3200 Sisk RD, Modesto, CA, 95356. Phone: (510) 332-3175. Providers update this record themselves, so call before visiting.

How can I verify Sylvester Nguyen's license?

NPPES lists California license number 33381, as entered by the provider. Search the California board that licenses this profession; the NPPES record confirms identity only.

How much does Sylvester Nguyen prescribe under Medicare Part D?

In 2024, Sylvester Nguyen had 35 Medicare Part D claims for 18 beneficiaries; the average among optometrist prescribers was 277. 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.