2026 NPPES data Retina Specialist (Ophthalmology) Physician NPI 1588636484 M.D.
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ERIC THOMAS, M.D.

Retina Specialist (Ophthalmology) Physician in SIOUX FALLS, South Dakota. 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
429
Medicare Part D claims · 149 beneficiaries · Retina Specialist (Ophthalmology) Physician avg: 558
Generic prescribing
61%
generic claims · 39% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$401.28
11 payments · CMS Open Payments (Sunshine Act)
What the federal data reveals: ERIC THOMAS, M.D. is a Retina Specialist (Ophthalmology) Physician ([object Object]) practicing in SIOUX FALLS, South Dakota with a Medicare Part D prescribing footprint of 429 claims across 149 beneficiaries — 39% brand-name prescribing . Industry payments of $401.28 across 11 transactions are disclosed under CMS Open Payments (Sunshine Act).

What stands out: ERIC THOMAS, M.D. filed 429 Medicare Part D claims in 2023 across SIOUX FALLS, South Dakota. Every figure on this page comes straight from federal CMS records, with no proprietary rating applied.

Board certification likely (heuristic — not verified)

ERIC THOMAS, 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).

ERIC THOMAS, M.D. at a glance

Quality data not reported

NPI registry status

Active

Issued 02/03/2006

NPI 1588636484

Primary specialty

Retina Specialist (Ophthalmology) Physician

Niche

913 US NPIs in this specialty

Medicare Part D claims

429 23% vs specialty avg

2023 prescription claims

Specialty avg: 558

Specialty distribution in South Dakota

How Retina Specialist (Ophthalmology) Physician compares to other specialties among South Dakota providers

South Dakota providers

Retina Specialist (Ophthalmology) Physician share within South Dakota

1. Retina Specialist (Ophthalmology) Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Retina Specialist (Ophthalmology) Physician share within South Dakota

Specialty board-certification context

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

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

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

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

ERIC THOMAS, M.D. is a Retina Specialist (Ophthalmology) Physician provider practicing in SIOUX FALLS, South Dakota, according to the CMS National Plan and Provider Enumeration System (NPPES). Credentials: M.D.. NPI: 1588636484. This profile includes practice location, specialty classification, and organizational affiliations from the CMS provider registry. Provider information is self-reported to CMS and updated monthly.

ERIC THOMAS, M.D. appears in the CMS NPPES registry as a Retina Specialist (Ophthalmology) Physician provider holding M.D. credentials at 6601 S MINNESOTA AVE STE 200, SIOUX FALLS, SD, 57108, with a listed phone of (605) 336-6294. NPI 1588636484 was issued on 02/03/2006. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what THOMAS 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 429 prescription claims written by this provider, covering 149 Medicare beneficiaries and totaling roughly $18K in drug spend, split 39% brand-name and 61% 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.

Retina Specialist (Ophthalmology) Physician is a narrow specialty nationwide, with 913 enrolled providers across 48 states and an average of 558 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

6601 S MINNESOTA AVE STE 200
SIOUX FALLS, SD 57108

Provider Details

NPI 1588636484
Specialty Retina Specialist (Ophthalmology) Physician
Credentials M.D.
Gender Male
NPI Issued 02/03/2006

Hospital and facility affiliations

Facilities where ERIC THOMAS, 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.

OPHTHALMOLOGY LTD
SIOUX FALLS, SD

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 ERIC THOMAS, M.D.. Source: openpaymentsdata.cms.gov.

Total received

$401

Largest payer

Alimera Sciences, 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.

Brand vs generic prescribing mix · Above average

ERIC THOMAS, M.D. — brand share 39.0%
Specialty average (est.)

39% brand-name claims vs 61% generic, on 429 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.

429
Total Claims
$18K
Total Drug Cost
149
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
616
Total Day Supply
16,933
Brand vs Generic
39% brand / 61% generic
Brand Drug Cost
$13K
Generic Drug Cost
$6K

Patient Demographics

Average Patient Age
71.8 years
Avg HCC Risk Score
1.28
Gender Split
52% female / 48% male

Top Prescribed Drugs (Medicare Part D)

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

Drug Claims
Prednisolone Acetate
132
Atropine Sulfate
114
Polymyxin B Sul-Trimethoprim
Polymyxin B Sulf/Trimethoprim
114
Timolol Maleate
15
Ofloxacin
14

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

Retina Specialist (Ophthalmology) Physician Overview

How ERIC THOMAS, M.D. fits within the Retina Specialist (Ophthalmology) Physician landscape nationally.

913
Retina Specialist (Ophthalmology) Physician Providers in US
48
States with Retina Specialist (Ophthalmology) Physician
558
Avg Claims per Provider

ERIC THOMAS, M.D.'s 429 claims are below the specialty average of 558.

Nearby Retina Specialist (Ophthalmology) Physician Providers in South Dakota

Other clinicians with the same primary specialty enrolled in South Dakota, drawn from the same CMS NPPES roster as THOMAS.

Compare Retina Specialist (Ophthalmology) Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is ERIC THOMAS, M.D.'s specialty?
ERIC THOMAS, M.D. specializes in Retina Specialist (Ophthalmology) Physician and practices in SIOUX FALLS, South Dakota. Credentials: M.D..
How much does ERIC THOMAS, M.D. prescribe under Medicare Part D?
In 2023, ERIC THOMAS, M.D. wrote 429 Medicare Part D claims totaling $18K in drug costs for 149 beneficiaries.
Where is ERIC THOMAS, M.D. located?
ERIC THOMAS, M.D. is located at 6601 S MINNESOTA AVE STE 200, SIOUX FALLS, SD, 57108. Phone: (605) 336-6294.
What is ERIC THOMAS, M.D.'s NPI number?
ERIC THOMAS, M.D.'s National Provider Identifier (NPI) is 1588636484, issued on 02/03/2006.
Does ERIC THOMAS, M.D. prescribe more brand-name or generic drugs?
ERIC THOMAS, M.D.'s prescribing is 39% brand-name and 61% generic drugs by claim count, with $13K in brand drug costs.
How many Retina Specialist (Ophthalmology) Physician providers are there in the US?
There are 913 Retina Specialist (Ophthalmology) Physician providers across 48 states in the US. The average Retina Specialist (Ophthalmology) Physician provider writes 558 Medicare Part D claims per year.
What drugs does ERIC THOMAS, M.D. prescribe most often?
Based on 2023 Medicare Part D data, ERIC THOMAS, M.D.'s most frequently prescribed drugs include Prednisolone Acetate, Atropine Sulfate, Polymyxin B Sul-Trimethoprim. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does ERIC THOMAS, M.D. accept Medicare?
ERIC THOMAS, M.D. appears in CMS Medicare data with 429 Part D claims and 149 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify ERIC THOMAS, M.D.'s credentials?
ERIC THOMAS, M.D.'s NPI is 1588636484 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