NPI registry status
Active
2026 NPPES data Hospitalist Physician NPI 1134418171 M.D.
Verify on CMS → Brian Apter, M.D.
Hospitalist Physician in Pasadena, California.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 17,950 in Hospitalist Physician, and covers specialty classification, practice address, and Medicare Part D prescribing data when reported. According to CMS, every field reflects the provider's official federal registration, see our methodology.
Federal data, no proprietary rating.
We show these CMS records as-is - no composite score, no star rating, no editorial opinion layered on top.
Prescribing volume
491
Medicare Part D claims · 174 beneficiaries · Hospitalist Physician avg: 940
What the federal data shows
Brian Apter, M.D. filed 491 Medicare Part D claims in 2024 as a Hospitalist Physician in Pasadena, California.
- 491
- Part D claims, 2024
- Likely
- board-certified (heuristic)
- ≥61st
- pct by Part D claim volume (lower-bound band)
Every figure on this page comes straight from federal CMS records (NPPES, Medicare Part D, MIPS, Open Payments) - no proprietary rating or editorial opinion is applied.
Federal trust snapshot
What official records show about Brian Apter, M.D.
Federal records show an active NPI with Medicare Part D prescribing activity — verifiable registry data, not a proprietary rating.
- Verified
NPI registry status
Active listing in the CMS National Provider Identifier Registry (NPI 1134418171), first enumerated 03/30/2011.
Source: CMS NPPES
- Reported
Medicare Part D participation
Filed 491 Medicare Part D prescription claims in the 2023 CMS public use file — indicates active Medicare prescribing participation.
Source: CMS Part D Prescriber PUF
- Reported
Board certification signal
Heuristic suggests board-certified status based on ABMS-eligible specialty taxonomy plus active CMS participation signals — not a direct ABMS verification.
- Reported
Hospital affiliations
1 CMS Care Compare hospital affiliation on record — practice footprint from the Doctors and Clinicians file.
Source: CMS Care Compare
- State context
State board disciplinary context
California statewide board action statistics are published annually — these figures describe aggregate state activity, not Brian Apter, M.D.'s individual license status. Verify directly with the state medical board.
Source: Medical Board of California annual report FY 2022-23
- Not in federal data
Individual sanction lookup
PlainDoctor does not publish per-provider disciplinary determinations. Confirm current license and any individual actions through the state medical board or FSMB verification service.
Source: State medical board / FSMB
This trust snapshot summarizes only what appears in federal CMS/NPPES public records. It is not a composite score, star rating, patient review, or clinical recommendation. PlainDoctor never fabricates reviews or AggregateRating schema.
Compare Apter with other Hospitalist Physician providers
Same primary specialty, same federal CMS NPPES roster.
Also enrolled in California
- Dr. Zina Abbas, M.D. Chula Vista, CA
- Dr. Mehrdad Abbasi, MD Rancho Mirage, CA
- Dr. Abdul Abdali, M.D. French Camp, CA
- Dr. Anwar Abdelhadi, M.D. Orange, CA
- Dr. Farid Abdelmalak, M.D. Santa Monica, CA
- Dr. Joseph Abdelmalek, M.D San Diego, CA
Other specialties in Pasadena: Behavior Technician (1,647) · Marriage & Family Therapist (977) · Rehabilitation Practitioner (912) · Student in an Organized Health Care Education/Training Program (825)
CMS NPPES provider registry desk
NPI 1134418171 · Hospitalist Physician
NPI-10 · ENUM-MID · TAX-MID · RX-LIGHT · BOOK-LIGHT · PHOTO-ENUM
- NPI-10 1134418171
- ENUM-MID 2011
- TAX-MID 18K Hospitalist Physician
- RX-LIGHT 491
- BOOK-LIGHT 1,901 in California
- PHOTO-ENUM Emmanuel Hernandez,… · 2011
Brian Apter, M.D.'s Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2024, across all CMS prescribers nationally
491 ≥ 61st percentile 61% of 1,416,883 prescribers are in lower value bands
Each bar is a band; taller bars hold more prescribers. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
The percentile is a conservative 100-claim band: it counts only prescribers in lower claim-volume bands. Medicare Part D claim volume is activity context, not a quality measure or recommendation. See methodology § corpus placement.
Source CMS Medicare Part D Prescriber Public Use File · 2024
✓
Board certification likely (heuristic, not verified)
Brian Apter, M.D. practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 1 hospital affiliation - signals consistent with board-certified status. For verified board certification, see CertificationMatters.org (the official ABMS public lookup).
What does the federal data show about Brian Apter, M.D.?
Quality data not reportedPrimary specialty
Hospitalist Physician
Medicare Part D claims
491 48% vs specialty avg
Specialty distribution in California
How Hospitalist Physician compares to other specialties among California providers
Board certification
Not published by CMS
CMS does not publish a per-provider board-certification field in NPPES. PlainDoctor does not have a reliable per-specialty certification rate to show for Hospitalist Physician. Verify directly:
How MIPS and board certification work
The Merit-based Incentive Payment System (MIPS) scores providers 0–100 across four performance categories: Quality, Cost, Promoting Interoperability, and Improvement Activities, weighted under 42 CFR §414.1380. Reporting is voluntary for many small practices, so absence of a MIPS score is not a quality signal.
Board certification through an ABMS or AOA member board signals voluntary post-licensure examination plus continuous Maintenance of Certification cycles. Verify any individual provider's status through certificationmatters.org (ABMS) or osteopathic.org (AOA).
Practice Address
Provider Details
| NPI | 1134418171 |
|---|---|
| Specialty | Hospitalist Physician |
| Credentials | M.D. |
| Gender | Male |
| NPI Issued | 03/30/2011 |
Hospital and facility affiliations
Facilities where Brian Apter, M.D. bills Medicare from. Star ratings (1-5) are CMS Hospital Compare's "Hospital overall rating" - a composite of mortality, readmission, patient experience, safety, timely care, and efficient use of medical imaging measures. Source: CMS Care Compare.
Southern California Permanente Medical Group
Riverside, CA
Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).
License & disciplinary context - California Medical Board of California, FY 2022-23
Aggregate state board data only, NOT a determination of any individual provider's status. The figures below describe statewide disciplinary activity across 148,769 California physician licenses in effect in FY 2022-23 - they are NOT specific to Brian Apter, M.D.. To verify Brian Apter, M.D.'s current license status, use the state board's own license search (see California license lookup), or the Federation of State Medical Boards (FSMB) verification service.
374
Administrative board actions, California FY 2022-23
2.51
Actions per 1,000 physician licenses in effect
California statewide rate
Probation
Most common action type
148 actions
Source: Medical Board of California Annual Report 2022-2023, page 18 (licenses in effect: page 12). Full breakdown by action type on the California discipline page.
Medicare Part D Prescribing Data
CMS Medicare Part D prescriber-level data for calendar year 2024.
491
Total Claims
$28K
Total Drug Cost
174
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 1,022.067
- Total Day Supply
- 27,712
- Generic Drug Cost
- $8K
- Antibiotic Claims
- 68
Patient Demographics
- Average Patient Age
- 76.6 years
- Avg HCC Risk Score
- 2.58
- Gender Split
- 51% female / 49% male
- Age Distribution
- <65: 13, 65-74: 58, 75-84: 67, 85+: 36
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2024. Based on Medicare Part D data only.
What Brian Apter, M.D. prescribes most
Top Medicare Part D drugs by claim count, 2024
- Furosemide
Furosemide
46 claims
- Hydralazine Hcl
Hydralazine Hcl
36 claims
- Metoprolol Tartrate
Metoprolol Tartrate
21 claims
- Amlodipine Besylate
Amlodipine Besylate
20 claims
- Atorvastatin Calcium
Atorvastatin Calcium
20 claims
- Potassium Chloride
Potassium Chloride
19 claims
- Bisoprolol Fumarate 16
Bisoprolol Fumarate
16 claims
- Cephalexin 14
Cephalexin
14 claims
| Drug | Claims |
|---|---|
| Furosemide | 46 |
| Hydralazine Hcl | 36 |
| Metoprolol Tartrate | 21 |
| Amlodipine Besylate | 20 |
| Atorvastatin Calcium | 20 |
| Potassium Chloride | 19 |
| Bisoprolol Fumarate | 16 |
| Cephalexin | 14 |
| Losartan Potassium | 14 |
| Omeprazole | 14 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Hospitalist Physician Overview
How Brian Apter, M.D. fits within the Hospitalist Physician landscape nationally.
17,950
Hospitalist Physician Providers in US
54
States with Hospitalist Physician
940
Avg Claims per Provider
Brian Apter, M.D.'s 491 claims are below the specialty average of 940.
Nationwide Hospitalist Physician peers with similar MIPS or enrollment year
Two federal-record peer sets for Apter, both outside California so the neighborhoods are not geographic containment.
Same NPPES enumeration year (2011)
Same-specialty clinicians who entered the NPI registry in the same calendar year, outside this state.
Nearby Hospitalist Physician Providers in California
Other clinicians with the same primary specialty enrolled in California, drawn from the same CMS NPPES roster as Apter.
One of 1,901 Hospitalist Physician providers enrolled in California, 11 are shown on this page.
Elijah Abdelmeseeh
Long Beach, CA
Dr. Homayoun Abdollahzadeh
M.D.
Rancho Mirage, CA
Merna Abdou
San Diego, CA
Dr. Rafik Abdou
M.D
Mission Hills, CA
Wajidah Abdul-Khabir
Duarte, CA
Compare Hospitalist Physician nationally: see state-by-state distribution →
Frequently Asked Questions
What is Brian Apter, M.D.'s specialty? ▼
Brian Apter, M.D. specializes in Hospitalist Physician and practices in Pasadena, California. Credentials: M.D..
How much does Brian Apter, M.D. prescribe under Medicare Part D? ▼
In 2024, Brian Apter, M.D. wrote 491 Medicare Part D claims totaling $28K in drug costs for 174 beneficiaries.
Where is Brian Apter, M.D. located? ▼
Brian Apter, M.D. is located at 393 E WALNUT ST, Pasadena, CA, 91188. Phone: (415) 310-1938.
What is Brian Apter, M.D.'s NPI number? ▼
Brian Apter, M.D.'s National Provider Identifier (NPI) is 1134418171, issued on 03/30/2011.
How many Hospitalist Physician providers are there in the US? ▼
There are 17,950 Hospitalist Physician providers across 54 states in the US. The average Hospitalist Physician provider writes 940 Medicare Part D claims per year.
What drugs does Brian Apter, M.D. prescribe most often? ▼
Based on 2024 Medicare Part D data, Brian Apter, M.D.'s most frequently prescribed drugs include Furosemide, Hydralazine Hcl, Metoprolol Tartrate. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Brian Apter, M.D. accept Medicare? ▼
Brian Apter, M.D. appears in CMS Medicare data with 491 Part D claims and 174 Medicare beneficiaries in 2024. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Brian Apter, M.D.'s credentials? ▼
Brian Apter, M.D.'s NPI is 1134418171 with credentials M.D.. You can verify this through the NPPES NPI Registry, check state medical board records, and confirm board certification through the ABMS or AOA.
Data Sources
View source datasets and methodology notes
- Provider Directory
- CMS National Plan and Provider Enumeration System (NPPES), download.cms.gov/nppes, updated monthly. Contains NPI, specialty, credentials, and practice location.
- Specialty Classification
- NUCC Health Care Provider Taxonomy (nucc.org), the industry standard for classifying provider specialties in Medicare and Medicaid billing.
- Prescribing Data
- CMS Medicare Part D Prescriber Public Use File (2024). Includes claims, drug costs, beneficiaries, and opioid prescribing rates.
- Limitations
- Provider data is self-reported to CMS. Prescribing data reflects Medicare Part D only and does not include commercial insurance, Medicaid, or cash prescriptions. Claims below 11 beneficiaries are suppressed by CMS for privacy.
See our complete data methodology for details on how we collect and process government data.
Data as of August 2026 (NPPES) / 2024 (Medicare Part D). Source: Centers for Medicare & Medicaid Services (CMS).
Disclaimer: Data from CMS NPPES and Medicare Part D. PlainDoctor does not rate or rank providers. Provider information is self-reported and may not be current. Always verify information directly with the provider. About · Methodology
Every figure on PlainDoctor is rendered directly from the federal CMS NPPES registry, Medicare Part D, MIPS, and Open Payments records, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of September 2026.