Warren Johnson, MD
NPI 1558521682 · Emergency Medicine Physician · Fort Irwin, CA
Enrolled with Medicare as Practitioner - Emergency Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Warren Johnson, MD is a Emergency Medicine Physician provider in Fort Irwin, CA (NPI 1558521682).
Provider details
- NPI number
- 1558521682
- Entity type
- Individual
- Primary specialty
- Emergency Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- Yes
- License
- A117174 (CA)
Specialties & taxonomies
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
18 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
462 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) |
|---|---|---|
| Emergency Department Visit With High Level of Medical Decision Making99285 | 234 | $169 |
| Routine Electrocardiogram (ecg) Using at Least 12 Leads With Interpretation and Report Only93010 | 134 | $8 |
| Critical Care, First 30-74 Minutes99291 | 48 | $206 |
| Emergency Department Visit With Moderate Level of Medical Decision Making99284 | 46 | $115 |
Typical Medicare-allowed amounts for these services range $8–$206 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, not a price quote and not what you would be billed. Medicare Part B covers roughly an eighth of all NPIs (65+ skew); services with fewer than 11 beneficiaries are suppressed by CMS. Source: CMS Medicare Physician & Other Practitioners, by Provider & Service.
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 11 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Ondansetronbrand: Ondansetron Odt | 38 | 38 |
| Levofloxacin | 34 | 33 |
| Oxycodone Hcl | 27 | 27 |
| Cephalexin | 21 | 20 |
| Cyclobenzaprine Hcl | 21 | 21 |
| Doxycycline Hyclate | 19 | 19 |
| Amoxicillin/Potassium Clavbrand: Amoxicillin-Clavulanate Potass | 16 | 16 |
Practice location
Mailing address
Registry dates
- Enumerated
- 2008-06-12
- Last updated
- 2018-06-14
Frequently asked questions
- What is Warren Johnson's NPI number?
- Warren Johnson's National Provider Identifier (NPI) is 1558521682, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Warren Johnson's specialty?
- Warren Johnson is listed in the NPPES registry with a primary specialty of Emergency Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Warren Johnson located?
- Warren Johnson's practice location on file with NPPES is Weed Army Community Hospital Bldg 166, Fort Irwin, CA 92310.
- What is Warren Johnson's phone number?
- The practice phone number listed in the NPPES registry for Warren Johnson is (760) 380-9407.
- Does Warren Johnson accept Medicare?
- Warren Johnson is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Warren Johnson's NPI active?
- Yes — Warren Johnson's NPI (1558521682) is active in the NPPES registry as of the last update on 2018-06-14.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.