James Nellen, MD
NPI 1174086748 · Anesthesiology Physician · Greenbrae, CA
Enrolled with Medicare as Practitioner - Anesthesiology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
James Nellen, MD is a Anesthesiology Physician provider in Greenbrae, CA (NPI 1174086748).
Provider details
- NPI number
- 1174086748
- Entity type
- Individual
- Primary specialty
- Anesthesiology PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- 75283 (WI)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
7 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)28% of score
160 Medicare services, 2024 (ranked within specialty)
Medicare volume is ranked against active providers in the same specialty. 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 does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Anesthesia for Other Procedure on Esophagus, Stomach, Or Upper Small Bowel Using an Endoscope00731 | 22 | $140 |
| Insertion of Artery Tube for Blood Sampling Or Infusion Through Skin36620 | 21 | $45 |
| Injection of Anesthetic Agent And/Or Steroid Into Arm Nerve Bundle (brachial Plexus)64415 | 18 | $65 |
| Injection of Local Anesthetic for Abdominal Wall Pain Control on Both Sides Using Imaging Guidance64488 | 18 | $64 |
| Anesthesia for X-Ray Or Radiation Therapy01922 | 15 | $222 |
| Ultrasonic Guidance for Blood Vessel Access76937 | 15 | $15 |
Practice location
Mailing address
Registry dates
- Enumerated
- 2019-04-10
- Last updated
- 2024-06-10
- Certified
- 2024-06-10
Frequently asked questions
- What is James Nellen's NPI number?
- James Nellen's National Provider Identifier (NPI) is 1174086748, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is James Nellen's specialty?
- James Nellen is listed in the NPPES registry with a primary specialty of Anesthesiology Physician (Allopathic & Osteopathic Physicians).
- Where is James Nellen located?
- James Nellen's practice location on file with NPPES is 250 Bon Air Rd, Greenbrae, CA 94904-1702.
- What is James Nellen's phone number?
- The practice phone number listed in the NPPES registry for James Nellen is (415) 925-7100.
- Does James Nellen accept Medicare?
- James Nellen is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is James Nellen's NPI active?
- Yes — James Nellen's NPI (1174086748) is active in the NPPES registry as of the last update on 2024-06-10.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.