G. Thomas Ruiz, MD
Obstetrics & Gynecology Physician · Fountain Valley, CA
G. Thomas Ruiz, MD is an obstetrics & gynecology physician with a practice address in Fountain Valley, California, and NPI 1518967330, issued on Jul 22, 2005. Check the license (California G69184, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- G. Thomas Ruiz
- Credential
- MD
- Primary taxonomy
- Obstetrics & Gynecology Physician 207V00000X
- License number
- G69184 CA
Self-reported in NPPES; status is on the state search - Practice location
- 18035 Brookhurst Street, Fountain Valley, CA 92708
- Phone
- (657) 241-9090
- Enumerated
- Jul 22, 2005
- Record last updated
- Oct 14, 2016 (not updated in 10 years: call before relying on the address or phone)
- Medicare enrollment
- Enrolled (PECOS I20070328000705); accepts Medicare assignment
- Medical or professional school
- University Of California, Irvine, California College Of Medicine, 1989
- Entity
- Type 1 · individual
8 nearest obstetrics & gynecology physician records → All 5,088 in California → Look up another NPI →
Also registered at 18035 Brookhurst Street
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Gerardo Bustillo, M.D.Obstetrics & Gynecology Physician1972631786
- Denise CastellanosMidwife1356587042
- Patricia Evans, CNMMidwife1760488126
- Lynn Hansen, CNMMidwife1063597219
- Annette McConnaughey, CNMMidwife1851398002
- Corry Varner, CNMAdvanced Practice Midwife1437347937
Verify G. Thomas Ruiz in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license G69184Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
24% fewer Medicare Part D claims than the average obstetrics & gynecology physician in 2024
125 Medicare Part D claims for 39 beneficiaries, against an average of 165 among the 28,733 providers of this specialty who prescribed in Part D. Brand-name drugs were 31% of claims.
Most prescribed
- Estradiol30 claims
- Estradiol (Once Weekly)13 claims
- Norethindrone Acetate12 claims
- Estradiol (Twice Weekly)11 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
- Memorialcare Medical FoundationFountain Valley, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
G. Thomas Ruiz among 5,088 obstetrics & gynecology physician records in California
G. Thomas Ruiz, MD is one of 5,088 obstetrics & gynecology physician records with a practice address in California. 74% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2005, is newer than 0% of them.
- NPI issued2005 · 0% of these records are older, 95% newer
- In a Medicare fileYes · 74% of these records are
- In the CMS Doctors and Clinicians fileYes · 53% of these records are
- Graduated1989 · median 2004 among the 2,700 with a school on file
- Record last updated2016 · 64% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207V00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
23 obstetrics & gynecology physician records list a practice address in Fountain Valley
They are 23 of the 2,190 NPPES records with a practice address in Fountain Valley, and 5,088 obstetrics & gynecology physician records in California.
All 5,088 in California → Every provider in Fountain Valley → Obstetrics & Gynecology Physician nationwide →
The 8 obstetrics & gynecology physician records with the nearest ZIP codes
- Gerardo Bustillo, M.D.Fountain Valley, CA 927081972631786
- Cynthia Cork, M.D.Fountain Valley, CA 927081134229602
- Ellen Fraser, M.D.Fountain Valley, CA 927081275598443
- Jamie Kim, M.D.Fountain Valley, CA 927081225187388
- Carol Levi, M.D.Fountain Valley, CA 927081497706907
- Minal Mehta, M.D.Fountain Valley, CA 927081780787580
- Sunita Moola, MDFountain Valley, CA 927081770770695
- Krystal Pham, MDFountain Valley, CA 927081710001763
Common questions
What is G. Thomas Ruiz, MD's NPI number?
G. Thomas Ruiz, MD's National Provider Identifier (NPI) is 1518967330, issued on Jul 22, 2005. An NPI identifies a provider in billing; it is not a license.
Where is G. Thomas Ruiz, MD located?
The NPPES record lists a practice address at 18035 Brookhurst Street, Fountain Valley, CA, 92708. Phone: (657) 241-9090. Providers update this record themselves, so call before visiting.
How can I verify G. Thomas Ruiz, MD's license?
NPPES lists California license number G69184, 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 G. Thomas Ruiz, MD prescribe under Medicare Part D?
In 2024, G. Thomas Ruiz, MD had 125 Medicare Part D claims for 39 beneficiaries; the average among obstetrics & gynecology physician prescribers was 165. 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.