Merl O'Brien, M.D.
NPI 1386687317 · Emergency Medicine Physician · Carmichael, CA
Merl O'Brien, M.D. is a Emergency Medicine Physician provider in Carmichael, CA (NPI 1386687317).
Provider details
- NPI number
- 1386687317
- Entity type
- Individual
- Primary specialty
- Emergency Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- G34781 (CA)
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
20 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
- 2006-06-14
- Last updated
- 2007-07-08
Frequently asked questions
- What is Merl O'Brien's NPI number?
- Merl O'Brien's National Provider Identifier (NPI) is 1386687317, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Merl O'Brien's specialty?
- Merl O'Brien is listed in the NPPES registry with a primary specialty of Emergency Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Merl O'Brien located?
- Merl O'Brien's practice location on file with NPPES is 4156 Manzanita Ave, Carmichael, CA 95608-1726.
- What is Merl O'Brien's phone number?
- The practice phone number listed in the NPPES registry for Merl O'Brien is (916) 483-5400.
- Is Merl O'Brien's NPI active?
- Yes — Merl O'Brien's NPI (1386687317) is active in the NPPES registry as of the last update on 2007-07-08.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.