Gregory Williams, M.D.
NPI 1891910659 · Psychiatry Physician · Corpus Christi, TX
Enrolled with Medicare as Practitioner - Psychiatry · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Gregory Williams, M.D. is a Psychiatry Physician provider in Corpus Christi, TX (NPI 1891910659).
Provider details
- NPI number
- 1891910659
- Entity type
- Individual
- Primary specialty
- Psychiatry PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- R0812 (TX)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure33% of score
19 yrs in NPPES registry
- Profile completeness33% of score
100% of core fields populated
- Practice footprint20% of score
2 documented practice locations
- Open Payments transparency13% of score
Has Open Payments disclosures (2024)
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 4 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Dextroamphetamine/Amphetaminebrand: Dextroamphetamine-Amphet Er | 61 | 11 |
| Dextroamphetamine/Amphetaminebrand: Dextroamphetamine-Amphetamine | 40 | — |
| Duloxetine Hcl | 17 | — |
| Sertraline Hcl | 13 | — |
Medicare Part D only. These counts cover prescriptions paid through Medicare Part D in 2024 — they do notinclude cash-pay, commercial-insurance, Medicaid, or Part B–administered drugs, and badly undercount high cash-pay categories (e.g. GLP-1 weight-loss, testosterone, and ED medications). Any drug with 10 or fewer claims is omitted by CMS, and beneficiary counts under 11 are suppressed — so a missing drug means no Part D record, never zero. This is a factual claims summary, not an endorsement, not medical advice, and not a consumer report. Source: CMS Medicare Part D Prescribers — by Provider and Drug.
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$25 across 1 record (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Additional practice locations (1)
- 151 Stagecoach Trl Ste 220San Marcos, TX 78666-3863Phone: (844) 824-8775
Registry dates
- Enumerated
- 2007-04-16
- Last updated
- 2026-05-08
- Certified
- 2026-05-08
Frequently asked questions
- What is Gregory Williams's NPI number?
- Gregory Williams's National Provider Identifier (NPI) is 1891910659, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Gregory Williams's specialty?
- Gregory Williams is listed in the NPPES registry with a primary specialty of Psychiatry Physician (Allopathic & Osteopathic Physicians).
- Where is Gregory Williams located?
- Gregory Williams's practice location on file with NPPES is 5734 Spohn Dr Ste 110, Corpus Christi, TX 78414-4116.
- What is Gregory Williams's phone number?
- The practice phone number listed in the NPPES registry for Gregory Williams is (903) 957-0082.
- Does Gregory Williams accept Medicare?
- Gregory Williams is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Gregory Williams's NPI active?
- Yes — Gregory Williams's NPI (1891910659) is active in the NPPES registry as of the last update on 2026-05-08.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.