Maruja Diaz Arjonilla, MD
NPI 1841481074 · Endocrinology, Diabetes & Metabolism Physician · Santa Ana, CA
Enrolled with Medicare as Practitioner - Endocrinology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Maruja Diaz Arjonilla, MD is a Endocrinology, Diabetes & Metabolism Physician provider in Santa Ana, CA (NPI 1841481074).
Provider details
- NPI number
- 1841481074
- Entity type
- Individual
- Primary specialty
- Endocrinology, Diabetes & Metabolism PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Female
- Sole proprietor
- No
- License
- A97144 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
18 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
3 documented practice locations
- Medicare service volume (vs. specialty peers)25% of score
462 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
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 .
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) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 259 | $136 |
| Continuous Monitoring of Blood Sugar Level in Tissue Fluid Using Sensor Under Skin With Interpretation and Report95251 | 64 | $35 |
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 35 Minutes99232 | 41 | $81 |
| Ultrasound Scan of Head and Neck Soft Tissue76536 | 32 | $98 |
| Blood Glucose (sugar) Test Performed By Hand-Held Instrument82962 | 21 | $3 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 54 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Levothyroxine Sodium | 424 | 116 |
| Metformin Hclbrand: Metformin Hcl Er | 340 | 103 |
| Insulin Glargine,hum.rec.anlogbrand: Lantus Solostar | 293 | 96 |
| Semaglutidebrand: Ozempic | 286 | 56 |
| Glipizidebrand: Glipizide Er | 274 | 71 |
| Pen Needle, Diabeticbrand: Nano 2nd Gen Pen Needle | 202 | 84 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$143 across 8 records (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Additional practice locations (2)
- 1160 Sunset BlvdRocklin, CA 85765-3772Phone: (916) 865-1000Fax: (816) 865-1005
- 1160 Sunset BlvdRocklin, CA 85765-3772Phone: (916) 865-1000Fax: (816) 865-1005
Registry dates
- Enumerated
- 2007-08-05
- Last updated
- 2020-10-21
- Certified
- 2020-10-21
Frequently asked questions
- What is Maruja Diaz Arjonilla's NPI number?
- Maruja Diaz Arjonilla's National Provider Identifier (NPI) is 1841481074, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Maruja Diaz Arjonilla's specialty?
- Maruja Diaz Arjonilla is listed in the NPPES registry with a primary specialty of Endocrinology, Diabetes & Metabolism Physician (Allopathic & Osteopathic Physicians).
- Where is Maruja Diaz Arjonilla located?
- Maruja Diaz Arjonilla's practice location on file with NPPES is 2212 E 4th St Ste 304, Santa Ana, CA 92705.
- What is Maruja Diaz Arjonilla's phone number?
- The practice phone number listed in the NPPES registry for Maruja Diaz Arjonilla is (714) 288-3230.
- Does Maruja Diaz Arjonilla accept Medicare?
- Maruja Diaz Arjonilla is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Maruja Diaz Arjonilla's NPI active?
- Yes — Maruja Diaz Arjonilla's NPI (1841481074) is active in the NPPES registry as of the last update on 2020-10-21.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.