2026 NPPES data Psychiatry Physician NPI 1265464374 MD
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SIDDHARTHA KUMAR, MD

Psychiatry Physician in DIAMOND BAR, California. CMS National Plan and Provider Enumeration System profile including specialty classification, practice address, and Medicare prescribing data when reported.

Federal data — no proprietary rating. PlainDoctor publishes the actual CMS NPPES and Medicare records — NPI registration, specialty, practice location, and prescribing data — without a composite score or editorial opinion on top. Every field traces to a federal source.
Prescribing volume
405
Medicare Part D claims · 51 beneficiaries · Psychiatry Physician avg: 1K

What the federal data shows

SIDDHARTHA KUMAR, MD filed 405 Medicare Part D claims in 2023 as a Psychiatry Physician in DIAMOND BAR, California.

405
Part D claims, 2023
Likely
board-certified (heuristic)

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.

SIDDHARTHA KUMAR, MD's Medicare Part D volume vs every U.S. prescriber

Total Medicare Part D claims, 2023 — across all CMS prescribers nationally

405 Top 38% higher than 62% of 1,370,886 prescribers

0–200: 670,926 prescribers (49%). Below this entry. 200–400: 182,923 prescribers (13%). Below this entry. 400–600: 90,619 prescribers (7%). This entry sits in this band. 600–800: 56,224 prescribers (4%). Above this entry. 800–1,000: 40,919 prescribers (3%). Above this entry. 1,000–1,200: 31,827 prescribers (2%). Above this entry. 1,200–1,400: 26,224 prescribers (2%). Above this entry. 1,400–1,600: 21,710 prescribers (2%). Above this entry. 1,600–1,800: 19,072 prescribers (1%). Above this entry. 1,800–2,000: 16,451 prescribers (1%). Above this entry. 2,000–2,200: 213,991 prescribers (16%). Above this entry. This provider 0 2K+ every Part D prescriber (claims/yr), bucketed by value

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 certification likely (heuristic — not verified)

SIDDHARTHA KUMAR, MD 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 SIDDHARTHA KUMAR, MD?

Quality data not reported

NPI registry status

Active

Issued 07/07/2006

NPI 1265464374

Primary specialty

Psychiatry Physician

High-volume

53,104 US NPIs in this specialty

Medicare Part D claims

405 61% vs specialty avg

2023 prescription claims

Specialty avg: 1,038

Specialty distribution in California

How Psychiatry Physician compares to other specialties among California providers

California providers

Psychiatry Physician share within California

1. Psychiatry Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Psychiatry Physician share within California

Specialty board-certification context

Estimated specialty board-certified rate — Psychiatry Physician (ABMS / AOA reference)

Quality data not reported
Est. board-certified rate
78%
Psychiatry Physician ABMS/AOA estimate

Est. board-certified rate (Psychiatry Physician) — ABMS / AOA estimate

0%100%78%
Est. board-certified rate (Psychiatry Physician) — ABMS / AOA estimate

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).

SIDDHARTHA KUMAR, MD appears in the CMS NPPES registry as a Psychiatry Physician provider holding MD credentials at 1336 BRIDGEGATE DR, DIAMOND BAR, CA, 91765, with a listed phone of (626) 960-4844. NPI 1265464374 was issued on 07/07/2006. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what KUMAR most recently submitted to CMS rather than a vetted directory listing, which is why patients should always confirm the practice is still at this location before scheduling.

Medicare Part D records for calendar year 2023 show 405 prescription claims written by this provider, covering 51 Medicare beneficiaries and totaling roughly $9K in drug spend. These figures capture only Medicare Part D — commercial insurance, Medicaid, and cash-pay prescriptions are not included, and any drug-beneficiary cell under 11 is suppressed by CMS for patient privacy.

Psychiatry Physician is a high-volume specialty nationwide, with 53,104 enrolled providers across 56 states and an average of 1,038 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

1336 BRIDGEGATE DR
DIAMOND BAR, CA 91765

Provider Details

NPI 1265464374
Specialty Psychiatry Physician
Credentials MD
Gender Male
NPI Issued 07/07/2006

Hospital and facility affiliations

Facilities where SIDDHARTHA KUMAR, MD 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
SAN DIMAS, 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 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 SIDDHARTHA KUMAR, MD. To verify SIDDHARTHA KUMAR, MD'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.

405
Total Claims
$9K
Total Drug Cost
51
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
945
Total Day Supply
27,948
Generic Drug Cost
$8K

Patient Demographics

Average Patient Age
63.9 years
Avg HCC Risk Score
0.94
Gender Split
65% female / 35% male
Age Distribution
<65: 18, 65-74: N/A, 75-84: 17, 85+: N/A

Top Prescribed Drugs (Medicare Part D)

Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.

What SIDDHARTHA KUMAR, MD prescribes most

Top Medicare Part D drugs by claim count, 2023

claims
Source CMS Medicare Part D Prescriber Public Use File As of 2023
Drug Claims
Trazodone Hcl
48
Clonazepam
32
Duloxetine Hcl
27
Escitalopram Oxalate
27
Lorazepam
26
Quetiapine Fumarate
25
Fluoxetine Hcl
24
Buspirone Hcl
22
Risperidone
17
Clozapine
12

* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.

Psychiatry Physician Overview

How SIDDHARTHA KUMAR, MD fits within the Psychiatry Physician landscape nationally.

53,104
Psychiatry Physician Providers in US
56
States with Psychiatry Physician
1,038
Avg Claims per Provider

SIDDHARTHA KUMAR, MD's 405 claims are below the specialty average of 1,038.

Nearby Psychiatry Physician Providers in California

Other clinicians with the same primary specialty enrolled in California, drawn from the same CMS NPPES roster as KUMAR.

Compare Psychiatry Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is SIDDHARTHA KUMAR, MD's specialty?
SIDDHARTHA KUMAR, MD specializes in Psychiatry Physician and practices in DIAMOND BAR, California. Credentials: MD.
How much does SIDDHARTHA KUMAR, MD prescribe under Medicare Part D?
In 2023, SIDDHARTHA KUMAR, MD wrote 405 Medicare Part D claims totaling $9K in drug costs for 51 beneficiaries.
Where is SIDDHARTHA KUMAR, MD located?
SIDDHARTHA KUMAR, MD is located at 1336 BRIDGEGATE DR, DIAMOND BAR, CA, 91765. Phone: (626) 960-4844.
What is SIDDHARTHA KUMAR, MD's NPI number?
SIDDHARTHA KUMAR, MD's National Provider Identifier (NPI) is 1265464374, issued on 07/07/2006.
How many Psychiatry Physician providers are there in the US?
There are 53,104 Psychiatry Physician providers across 56 states in the US. The average Psychiatry Physician provider writes 1,038 Medicare Part D claims per year.
What drugs does SIDDHARTHA KUMAR, MD prescribe most often?
Based on 2023 Medicare Part D data, SIDDHARTHA KUMAR, MD's most frequently prescribed drugs include Trazodone Hcl, Clonazepam, Duloxetine Hcl. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does SIDDHARTHA KUMAR, MD accept Medicare?
SIDDHARTHA KUMAR, MD appears in CMS Medicare data with 405 Part D claims and 51 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify SIDDHARTHA KUMAR, MD's credentials?
SIDDHARTHA KUMAR, MD's NPI is 1265464374 with credentials MD. 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

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