2026 NPPES data Ophthalmology Physician NPI 1083871974 M.D.
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BRIAN LARSEN, M.D.

Ophthalmology Physician in LOMBARD, Illinois. 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
513
Medicare Part D claims · 183 beneficiaries · Ophthalmology Physician avg: 1K
Generic prescribing
53%
generic claims · 47% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$7.8K
31 payments · CMS Open Payments (Sunshine Act)

What the federal data shows

BRIAN LARSEN, M.D. filed 513 Medicare Part D claims in 2023 as a Ophthalmology Physician in LOMBARD, Illinois, prescribing 53% generic.

513
Part D claims, 2023
53%
generic prescribing
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.

BRIAN LARSEN, M.D.'s Medicare Part D volume vs every U.S. prescriber

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

513 Top 34% higher than 66% 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)

BRIAN LARSEN, M.D. practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 2 hospital affiliations — 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 LARSEN, M.D.?

Quality data not reported

NPI registry status

Active

Issued 05/19/2008

NPI 1083871974

Primary specialty

Ophthalmology Physician

Mid-sized

22,090 US NPIs in this specialty

Medicare Part D claims

513 64% vs specialty avg

2023 prescription claims

Specialty avg: 1,420

Specialty distribution in Illinois

How Ophthalmology Physician compares to other specialties among Illinois providers

Illinois providers

Ophthalmology Physician share within Illinois

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

Specialty board-certification context

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

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

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

0%100%78%
Est. board-certified rate (Ophthalmology 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).

BRIAN LARSEN, M.D. appears in the CMS NPPES registry as a Ophthalmology Physician provider holding M.D. credentials at 477 E BUTTERFIELD RD STE 105, LOMBARD, IL, 60148, with a listed phone of (773) 943-7425. NPI 1083871974 was issued on 05/19/2008. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what LARSEN 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 513 prescription claims written by this provider, covering 183 Medicare beneficiaries and totaling roughly $57K in drug spend, split 47% brand-name and 53% generic by claim count. 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.

Ophthalmology Physician is a mid-sized specialty nationwide, with 22,090 enrolled providers across 56 states and an average of 1,420 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

477 E BUTTERFIELD RD STE 105
LOMBARD, IL 60148

Provider Details

NPI 1083871974
Specialty Ophthalmology Physician
Credentials M.D.
Gender Male
NPI Issued 05/19/2008

Hospital and facility affiliations

Facilities where BRIAN LARSEN, 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.

COOK COUNTY
CHICAGO, IL
TENNENBAUM AND ANSTADT, LTD
MELROSE PARK, IL

Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).

Industry payments received (2024) — CMS Open Payments transparency data

The federal Physician Payments Sunshine Act (part of the Affordable Care Act) requires drug and medical-device manufacturers + group purchasing organizations to publicly report payments and other transfers of value to physicians and teaching hospitals. The data below covers 2024 for BRIAN LARSEN, M.D.. Source: openpaymentsdata.cms.gov.

Total received

$7.8K

Largest payer

Regeneron Pharmaceuticals, Inc.

Most common payment type

Food and Beverage

Industry payments are not necessarily indicators of bias — they include research funding, consulting fees for evidence-based work, royalties for inventions, food at conferences, and similar items. The disclosure exists for transparency. Read our methodology for how we interpret this data.

License & disciplinary context — Illinois IDFPR 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 ~42K Illinois medical licensees in 2023 — they are NOT specific to BRIAN LARSEN, M.D.. To verify BRIAN LARSEN, M.D.'s current license status, search the IDFPR public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.

106
Total board actions, Illinois 2023
Across 103 cases
2.52
Actions per 1,000 licensees
Illinois statewide rate
probation
Most common action type
38 cases

IDFPR 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 Illinois disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.

Brand vs generic prescribing mix · Above average

BRIAN LARSEN, M.D. — brand share 47.0%
Specialty average (est.)

47% brand-name claims vs 53% generic, on 513 2023 Medicare Part D claims.

The federal Medicare Part D Generic Dispensing Rate national benchmark sits near 90% generic / 10% brand for primary-care prescribers, per CMS Office of the Actuary 2024 estimates. Higher brand share is common in specialty prescribing where generic equivalents are not available.

Medicare Part D Prescribing Data

CMS Medicare Part D prescriber-level data for calendar year 2023.

513
Total Claims
$57K
Total Drug Cost
183
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
889
Total Day Supply
24,596
Brand vs Generic
47% brand / 53% generic
Brand Drug Cost
$41K
Generic Drug Cost
$16K

Patient Demographics

Average Patient Age
76.9 years
Avg HCC Risk Score
1.55
Gender Split
55% female / 45% male

Top Prescribed Drugs (Medicare Part D)

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

What BRIAN LARSEN, M.D. 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
Latanoprost
126
Prednisolone Acetate
68
Dorzolamide-Timolol
Dorzolamide Hcl/Timolol Maleat
45
Prolensa
Bromfenac Sodium
33
Moxifloxacin
Moxifloxacin Hcl
28
Bromfenac Sodium
26
Difluprednate
24
Erythromycin
Erythromycin Base
24
Timolol Maleate
19
Brimonidine Tartrate
16

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

Ophthalmology Physician Overview

How BRIAN LARSEN, M.D. fits within the Ophthalmology Physician landscape nationally.

22,090
Ophthalmology Physician Providers in US
56
States with Ophthalmology Physician
1,420
Avg Claims per Provider

BRIAN LARSEN, M.D.'s 513 claims are below the specialty average of 1,420.

Nearby Ophthalmology Physician Providers in Illinois

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

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

Frequently Asked Questions

What is BRIAN LARSEN, M.D.'s specialty?
BRIAN LARSEN, M.D. specializes in Ophthalmology Physician and practices in LOMBARD, Illinois. Credentials: M.D..
How much does BRIAN LARSEN, M.D. prescribe under Medicare Part D?
In 2023, BRIAN LARSEN, M.D. wrote 513 Medicare Part D claims totaling $57K in drug costs for 183 beneficiaries.
Where is BRIAN LARSEN, M.D. located?
BRIAN LARSEN, M.D. is located at 477 E BUTTERFIELD RD STE 105, LOMBARD, IL, 60148. Phone: (773) 943-7425.
What is BRIAN LARSEN, M.D.'s NPI number?
BRIAN LARSEN, M.D.'s National Provider Identifier (NPI) is 1083871974, issued on 05/19/2008.
Does BRIAN LARSEN, M.D. prescribe more brand-name or generic drugs?
BRIAN LARSEN, M.D.'s prescribing is 47% brand-name and 53% generic drugs by claim count, with $41K in brand drug costs.
How many Ophthalmology Physician providers are there in the US?
There are 22,090 Ophthalmology Physician providers across 56 states in the US. The average Ophthalmology Physician provider writes 1,420 Medicare Part D claims per year.
What drugs does BRIAN LARSEN, M.D. prescribe most often?
Based on 2023 Medicare Part D data, BRIAN LARSEN, M.D.'s most frequently prescribed drugs include Latanoprost, Prednisolone Acetate, Dorzolamide-Timolol. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does BRIAN LARSEN, M.D. accept Medicare?
BRIAN LARSEN, M.D. appears in CMS Medicare data with 513 Part D claims and 183 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify BRIAN LARSEN, M.D.'s credentials?
BRIAN LARSEN, M.D.'s NPI is 1083871974 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

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