Douglas Williamson, DNP
NPI 1386240844 · Psychiatric/Mental Health Registered Nurse · San Luis Obispo, CA
Enrolled with Medicare as Practitioner - Nurse Practitioner · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Douglas Williamson, DNP is a Psychiatric/Mental Health Registered Nurse provider in San Luis Obispo, CA (NPI 1386240844).
Provider details
- NPI number
- 1386240844
- Entity type
- Individual
- Primary specialty
- Psychiatric/Mental Health Registered NurseNursing Service Providers
- Credential
- DNP
- Sex
- Male
- Sole proprietor
- No
- License
- NP95016180 (CA)
Specialties & taxonomies
Nursing Service Providers
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
5 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
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 · 19 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Lamotrigine | 59 | — |
| Bupropion Hclbrand: Bupropion Xl | 54 | — |
| Trazodone Hcl | 52 | 13 |
| Escitalopram Oxalate | 39 | 11 |
| Duloxetine Hcl | 38 | — |
| Lurasidone Hcl | 33 | — |
| Sertraline Hcl | 31 |
Practice location
Mailing address
Registry dates
- Enumerated
- 2020-12-09
- Last updated
- 2025-03-20
- Certified
- 2025-03-20
Frequently asked questions
- What is Douglas Williamson's NPI number?
- Douglas Williamson's National Provider Identifier (NPI) is 1386240844, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Douglas Williamson's specialty?
- Douglas Williamson is listed in the NPPES registry with a primary specialty of Psychiatric/Mental Health Registered Nurse (Nursing Service Providers).
- Where is Douglas Williamson located?
- Douglas Williamson's practice location on file with NPPES is 1304 Ella St Ste B, San Luis Obispo, CA 93401-4166.
- What is Douglas Williamson's phone number?
- The practice phone number listed in the NPPES registry for Douglas Williamson is (805) 541-6000.
- Does Douglas Williamson accept Medicare?
- Douglas Williamson is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Douglas Williamson's NPI active?
- Yes — Douglas Williamson's NPI (1386240844) is active in the NPPES registry as of the last update on 2025-03-20.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.