NPPES file of Aug 9, 2026

Tarquin Siam Williams, PA-C

Physician Assistant · Cathedral City, CA

Tarquin Siam Williams, PA-C is a physician assistant with a practice address in Cathedral City, California, and NPI 1750539391, issued on Sep 8, 2008. Check the license (California PA19872, 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
1750539391
Name
Tarquin Siam Williams
Credential
PA-C
Primary taxonomy
Physician Assistant 363A00000X
License number
PA19872 CA
Self-reported in NPPES; status is on the state search
Practice location
69175 Ramon RD Bldg A, Cathedral City, CA 92234
Phone
(760) 321-6776
Enumerated
Sep 8, 2008
Record last updated
Sep 26, 2023
Medicare enrollment
Enrolled (PECOS I20111114000174); 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.
Download card Updates feed

Also registered at 69175 Ramon RD Bldg A

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

  1. Marlyne Abon, NURSE PRACTITIONERNurse Practitioner1982003604
  2. Kenneth Acha, M.D.Family Medicine Physician1174900211
  3. Jayne Ranee AntolinFamily Nurse Practitioner1306351689
  4. Christine Au, CPNPPediatric Nurse Practitioner1487230843
  5. Jose Banuelos, PMHNP-BC, FNP-CPsychiatric/Mental Health Nurse Practitioner1972165660
  6. Emma Bermudez, NPFamily Nurse Practitioner1275296360

Verify Tarquin Siam Williams 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 PA19872
    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

PlainDoctor does not match the HHS-OIG exclusion list to individual records: most entries carry no NPI. Search the OIG exclusion list by name.

Is this page about you? You can ask us to correct, restrict or remove it: how.

28% fewer Medicare Part D claims than the average physician assistant in 2024

595 Medicare Part D claims for 421 beneficiaries, against an average of 830 among the 101,058 providers of this specialty who prescribed in Part D. 32 claims were for opioids.

  1. Tarquin Williams595
  2. Specialty average830

Most prescribed

  1. Prednisone118 claims
  2. Cefadroxil45 claims
  3. Amoxicillin-Clavulanate Potass41 claims
  4. Doxycycline Monohydrate40 claims
  5. Azithromycin33 claims
  6. Albuterol Sulfate Hfa24 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. Southern California Permanente Medical GroupRiverside, CA

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

Tarquin Siam Williams among 14,451 physician assistant records in California

Tarquin Siam Williams, PA-C is one of 14,451 physician assistant records with a practice address in California. 75% 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 22% of them.

  • NPI issued2008 · 22% of these records are older, 75% newer
  • In a Medicare fileYes · 75% of these records are
  • In the CMS Doctors and Clinicians fileYes · 50% of these records are
  • Graduated2007 · median 2018 among the 7,214 with a school on file
  • Record last updated2023 · 40% of these records were not updated in five years or more

Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 363A00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).

9 physician assistant records list a practice address in Cathedral City

They are 9 of the 362 NPPES records with a practice address in Cathedral City, and 14,451 physician assistant records in California.

The 8 physician assistant records with the nearest ZIP codes

  1. Donna Ellamil-Lejarde, PACathedral City, CA 922341558021832
  2. Paul Gonzales, PA-CCathedral City, CA 922341992248207
  3. Kristopher Keene, PA-CCathedral City, CA 922341336190172
  4. Elizabeth Labha, PA-CCathedral City, CA 922341477824225
  5. Sydney Lopez, PA-CCathedral City, CA 922341538869862
  6. Elizabeth Loverso, PA-CCathedral City, CA 922341215114426
  7. Erik Luansing, PA-CCathedral City, CA 922341477542686
  8. Claudia Salcido, PA-CCathedral City, CA 922341821357955

Common questions

What is Tarquin Siam Williams, PA-C's NPI number?

Tarquin Siam Williams, PA-C's National Provider Identifier (NPI) is 1750539391, issued on Sep 8, 2008. An NPI identifies a provider in billing; it is not a license.

Where is Tarquin Siam Williams, PA-C located?

The NPPES record lists a practice address at 69175 Ramon RD Bldg A, Cathedral City, CA, 92234. Phone: (760) 321-6776. Providers update this record themselves, so call before visiting.

How can I verify Tarquin Siam Williams, PA-C's license?

NPPES lists California license number PA19872, as entered by the provider. Search the California board that licenses this profession; the NPPES record confirms identity only.

How much does Tarquin Siam Williams, PA-C prescribe under Medicare Part D?

In 2024, Tarquin Siam Williams, PA-C had 595 Medicare Part D claims for 421 beneficiaries; the average among physician assistant prescribers was 830. 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.