Gerin River, MD
NPI 1831408921 · Emergency Medicine Physician · Oakland, CA
Enrolled with Medicare as Practitioner - Emergency Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Gerin River, MD is a Emergency Medicine Physician provider in Oakland, CA (NPI 1831408921).
Provider details
- NPI number
- 1831408921
- Entity type
- Individual
- Primary specialty
- Emergency Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- Yes
- License
- A116048 (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
15 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 · 1 distinct drug on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Dexamethasone | 14 | 14 |
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.
Practice location
Mailing address
Registry dates
- Enumerated
- 2010-10-07
- Last updated
- 2022-01-21
- Certified
- 2022-01-21
Frequently asked questions
- What is Gerin River's NPI number?
- Gerin River's National Provider Identifier (NPI) is 1831408921, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Gerin River's specialty?
- Gerin River is listed in the NPPES registry with a primary specialty of Emergency Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Gerin River located?
- Gerin River's practice location on file with NPPES is 275 W Macarthur, Oakland, CA 94611-5641.
- What is Gerin River's phone number?
- The practice phone number listed in the NPPES registry for Gerin River is (510) 752-1000.
- Does Gerin River accept Medicare?
- Gerin River is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Gerin River's NPI active?
- Yes — Gerin River's NPI (1831408921) is active in the NPPES registry as of the last update on 2022-01-21.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.