NPI registry status
Active
2026 NPPES data Hematology (Internal Medicine) Physician NPI 1326050758 M.D.
Verify on CMS → Leon Rabinowitz, M.D.
Hematology (Internal Medicine) Physician in San Jose, 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 1,451 in Hematology (Internal Medicine) 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
73
Medicare Part D claims · 23 beneficiaries · Hematology (Internal Medicine) Physician avg: 693
Compiled from official public sources by the PlainDoctor editorial team.
What the federal data shows
Leon Rabinowitz, M.D. filed 73 Medicare Part D claims in 2023 as a Hematology (Internal Medicine) Physician in San Jose, California.
- 73
- Part D claims, 2023
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.
Leon Rabinowitz, M.D.'s Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
73 0th percentile higher than 0% of 1,370,886 prescribers
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.
Source CMS Medicare Part D Prescriber Public Use File · 2023
◑
Board-eligible specialty (heuristic, not verified)
Leon Rabinowitz, M.D. practices in an ABMS-board-eligible specialty but we don't have enough CMS-participation signals to confirm active board-certified status. Consult CertificationMatters.org (the official ABMS public lookup).
What does the federal data show about Leon Rabinowitz, M.D.?
Quality data not reportedPrimary specialty
Hematology (Internal Medicine) Physician
Medicare Part D claims
73 89% vs specialty avg
Specialty distribution in California
How Hematology (Internal Medicine) 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 Hematology (Internal Medicine) 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).
Leon Rabinowitz, M.D. appears in the CMS NPPES registry as a Hematology (Internal Medicine) Physician provider holding M.D. credentials at 4850 UNION AVE, San Jose, CA, 95124, with a listed phone of (408) 947-1233. NPI 1326050758 was issued on 08/13/2006.
Medicare Part D records for calendar year 2023 show 73 prescription claims written by this provider, covering 23 Medicare beneficiaries and totaling roughly $2K in drug spend.
Hematology (Internal Medicine) Physician is a narrow specialty nationwide, with 1,451 enrolled providers across 50 states and an average of 693 Part D claims per prescriber, so the context for interpreting these metrics differs meaningfully from a primary-care baseline.
Important: PlainDoctor is a directory of publicly available government data, not medical advice, a malpractice database, or a quality rating. Inclusion here does not imply a recommendation, and absence of complaints or sanctions on this page does not mean none exist, always verify credentials through the NPPES NPI Registry, your state medical board, and the ABMS or AOA before making healthcare decisions.
Practice Address
Provider Details
| NPI | 1326050758 |
|---|---|
| Specialty | Hematology (Internal Medicine) Physician |
| Credentials | M.D. |
| Gender | Male |
| NPI Issued | 08/13/2006 |
License & disciplinary context - California MBC 2023 annual report
Aggregate state board data only, NOT a determination of any individual provider's status. The figures below describe statewide disciplinary activity across all ~150K California medical licensees in 2023 - they are NOT specific to Leon Rabinowitz, M.D.. To verify Leon Rabinowitz, M.D.'s current license status, search the MBC public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.
576
Total board actions, California 2023
Across 556 cases
3.84
Actions per 1,000 licensees
California statewide rate
probation
Most common action type
186 cases
MBC publishes annual disciplinary statistics as part of public-record reporting under each state's Administrative Procedure Act. See the full breakdown by action type and year on the California disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.
Medicare Part D Prescribing Data
CMS Medicare Part D prescriber-level data for calendar year 2023.
73
Total Claims
$2K
Total Drug Cost
23
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 74
- Total Day Supply
- 1,392
- Generic Drug Cost
- $822
Patient Demographics
- Average Patient Age
- 87.5 years
- Avg HCC Risk Score
- 2.53
- Age Distribution
- <65: 0, 65-74: N/A, 75-84: N/A, 85+: 17
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
| Drug | Claims |
|---|---|
| Levothyroxine Sodium | 14 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
More Hematology (Internal Medicine) Physician in CA →
All providers in California →
Compare specialties →
Hematology (Internal Medicine) Physician Overview
How Leon Rabinowitz, M.D. fits within the Hematology (Internal Medicine) Physician landscape nationally.
1,451
Hematology (Internal Medicine) Physician Providers in US
50
States with Hematology (Internal Medicine) Physician
693
Avg Claims per Provider
Leon Rabinowitz, M.D.'s 73 claims are below the specialty average of 693.
Nearby Hematology (Internal Medicine) Physician Providers in California
Other clinicians with the same primary specialty enrolled in California, drawn from the same CMS NPPES roster as Rabinowitz.
Dr. Haifaa Abdulhaq
MD
Fresno, CA
Dr. John Adamson
MD
San Diego, CA
Dr. Idoroenyi Amanam
M.D.
Duarte, CA
Dr. Ian Anderson
M.D.
Santa Rosa, CA
Dr. Sally Arai
MD
Stanford, CA
Compare Hematology (Internal Medicine) Physician nationally: see state-by-state distribution →
Before you book an appointment
Use this federal record as your verification checklist, not as a recommendation.
- Confirm the NPI record is current in the official CMS registry, providers update their own NPPES details, and moves can lag. Verify this NPI
- Check the active license and any disciplinary history with the California medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Hematology (Internal Medicine) Physician peer on Medicare volume and prescribing patterns. Compare providers
Medicare Part D and MIPS figures describe practice patterns in federal programs only, they are not quality ratings, and PlainDoctor does not rate, rank, or recommend providers.
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Frequently Asked Questions
What is Leon Rabinowitz, M.D.'s specialty? ▼
Leon Rabinowitz, M.D. specializes in Hematology (Internal Medicine) Physician and practices in San Jose, California. Credentials: M.D..
How much does Leon Rabinowitz, M.D. prescribe under Medicare Part D? ▼
In 2023, Leon Rabinowitz, M.D. wrote 73 Medicare Part D claims totaling $2K in drug costs for 23 beneficiaries.
Where is Leon Rabinowitz, M.D. located? ▼
Leon Rabinowitz, M.D. is located at 4850 UNION AVE, San Jose, CA, 95124. Phone: (408) 947-1233.
What is Leon Rabinowitz, M.D.'s NPI number? ▼
Leon Rabinowitz, M.D.'s National Provider Identifier (NPI) is 1326050758, issued on 08/13/2006.
How many Hematology (Internal Medicine) Physician providers are there in the US? ▼
There are 1,451 Hematology (Internal Medicine) Physician providers across 50 states in the US. The average Hematology (Internal Medicine) Physician provider writes 693 Medicare Part D claims per year.
What drugs does Leon Rabinowitz, M.D. prescribe most often? ▼
Based on 2023 Medicare Part D data, Leon Rabinowitz, M.D.'s most frequently prescribed drugs include Levothyroxine Sodium. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Leon Rabinowitz, M.D. accept Medicare? ▼
Leon Rabinowitz, M.D. appears in CMS Medicare data with 73 Part D claims and 23 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Leon Rabinowitz, M.D.'s credentials? ▼
Leon Rabinowitz, M.D.'s NPI is 1326050758 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 (2023). 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 April 2026 (NPPES) / 2023 (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
Compiled from official public sources by the PlainDoctor editorial team.
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 May 2026.