Patrick Twomey, M.D.
NPI 1265639454 · Internal Medicine Physician · South San Francisco, CA
Enrolled with Medicare as Order and Referring Only - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Patrick Twomey, M.D. is a Internal Medicine Physician provider in South San Francisco, CA (NPI 1265639454).
Provider details
- NPI number
- 1265639454
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- 0101245204 (VA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
18 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.
Practice location
Mailing address
Registry dates
- Enumerated
- 2007-06-29
- Last updated
- 2018-02-15
Frequently asked questions
- What is Patrick Twomey's NPI number?
- Patrick Twomey's National Provider Identifier (NPI) is 1265639454, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Patrick Twomey's specialty?
- Patrick Twomey is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Patrick Twomey located?
- Patrick Twomey's practice location on file with NPPES is 1 Dna Way, South San Francisco, CA 94080-4918.
- What is Patrick Twomey's phone number?
- The practice phone number listed in the NPPES registry for Patrick Twomey is (650) 225-2580.
- Does Patrick Twomey accept Medicare?
- Patrick Twomey is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Patrick Twomey's NPI active?
- Yes — Patrick Twomey's NPI (1265639454) is active in the NPPES registry as of the last update on 2018-02-15.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.