2026 NPPES data Gastroenterology Physician NPI 1952411670 M.D.
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LUIS ARMSTRONG, M.D.

Gastroenterology Physician in CASPER, Wyoming. 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
2K
Medicare Part D claims · 581 beneficiaries · Gastroenterology Physician avg: 833
Generic prescribing
75%
generic claims · 25% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$376.65
17 payments · CMS Open Payments (Sunshine Act)
What the federal data reveals: LUIS ARMSTRONG, M.D. is a Gastroenterology Physician ([object Object]) practicing in CASPER, Wyoming with a Medicare Part D prescribing footprint of 2K claims across 581 beneficiaries — 25% brand-name prescribing . Industry payments of $376.65 across 17 transactions are disclosed under CMS Open Payments (Sunshine Act).

What stands out: LUIS ARMSTRONG, M.D. filed 1,552 Medicare Part D claims in 2023 across CASPER, Wyoming. Every figure on this page comes straight from federal CMS records, with no proprietary rating applied.

Board certification likely (heuristic — not verified)

LUIS ARMSTRONG, 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).

LUIS ARMSTRONG, M.D. at a glance

Quality data not reported

NPI registry status

Active

Issued 08/30/2006

NPI 1952411670

Primary specialty

Gastroenterology Physician

Mid-sized

16,567 US NPIs in this specialty

Medicare Part D claims

1,552 86% vs specialty avg

2023 prescription claims

Specialty avg: 833

Specialty distribution in Wyoming

How Gastroenterology Physician compares to other specialties among Wyoming providers

Wyoming providers

Gastroenterology Physician share within Wyoming

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

Specialty board-certification context

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

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

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

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

LUIS ARMSTRONG, M.D. is a Gastroenterology Physician provider practicing in CASPER, Wyoming, according to the CMS National Plan and Provider Enumeration System (NPPES). Credentials: M.D.. NPI: 1952411670. 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.

LUIS ARMSTRONG, M.D. appears in the CMS NPPES registry as a Gastroenterology Physician provider holding M.D. credentials at 1026 E 2ND ST, CASPER, WY, 82601, with a listed phone of (073) 333-0002. NPI 1952411670 was issued on 08/30/2006. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what ARMSTRONG 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 1,552 prescription claims written by this provider, covering 581 Medicare beneficiaries and totaling roughly $687K in drug spend, split 25% brand-name and 75% 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.

Gastroenterology Physician is a mid-sized specialty nationwide, with 16,567 enrolled providers across 54 states and an average of 833 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

1026 E 2ND ST
CASPER, WY 82601

Provider Details

NPI 1952411670
Specialty Gastroenterology Physician
Credentials M.D.
Gender Male
NPI Issued 08/30/2006

Hospital and facility affiliations

Facilities where LUIS ARMSTRONG, 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.

DIGESTIVE CARE SPECIALISTS, LLC
CASPER, WY

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 LUIS ARMSTRONG, M.D.. Source: openpaymentsdata.cms.gov.

Total received

$377

Largest payer

Janssen Biotech, 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

LUIS ARMSTRONG, M.D. — brand share 25.0%
Specialty average (est.)

25% brand-name claims vs 75% generic, on 1,552 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.

1,552
Total Claims
$687K
Total Drug Cost
581
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
3,109
Total Day Supply
80,647
Brand vs Generic
25% brand / 75% generic
Brand Drug Cost
$616K
Generic Drug Cost
$70K
Antibiotic Claims
49

Patient Demographics

Average Patient Age
69.7 years
Avg HCC Risk Score
1.90
Gender Split
62% female / 38% male
Age Distribution
<65: 102, 65-74: 325, 75-84: 133, 85+: 21

Top Prescribed Drugs (Medicare Part D)

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

Drug Claims
Omeprazole
413
Famotidine
230
Pantoprazole Sodium
91
Clenpiq
Sod Picosulf/Mag Ox/Citric Ac
56
Creon
Lipase/Protease/Amylase
35
Mesalamine
32
Sucralfate
28
Budesonide Dr
Budesonide
24
Ondansetron Hcl
20
Lactulose
19

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

Gastroenterology Physician Overview

How LUIS ARMSTRONG, M.D. fits within the Gastroenterology Physician landscape nationally.

16,567
Gastroenterology Physician Providers in US
54
States with Gastroenterology Physician
833
Avg Claims per Provider

LUIS ARMSTRONG, M.D.'s 1,552 claims are above the specialty average of 833.

Nearby Gastroenterology Physician Providers in Wyoming

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

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

Frequently Asked Questions

What is LUIS ARMSTRONG, M.D.'s specialty?
LUIS ARMSTRONG, M.D. specializes in Gastroenterology Physician and practices in CASPER, Wyoming. Credentials: M.D..
How much does LUIS ARMSTRONG, M.D. prescribe under Medicare Part D?
In 2023, LUIS ARMSTRONG, M.D. wrote 1,552 Medicare Part D claims totaling $687K in drug costs for 581 beneficiaries.
Where is LUIS ARMSTRONG, M.D. located?
LUIS ARMSTRONG, M.D. is located at 1026 E 2ND ST, CASPER, WY, 82601. Phone: (073) 333-0002.
What is LUIS ARMSTRONG, M.D.'s NPI number?
LUIS ARMSTRONG, M.D.'s National Provider Identifier (NPI) is 1952411670, issued on 08/30/2006.
Does LUIS ARMSTRONG, M.D. prescribe more brand-name or generic drugs?
LUIS ARMSTRONG, M.D.'s prescribing is 25% brand-name and 75% generic drugs by claim count, with $616K in brand drug costs.
How many Gastroenterology Physician providers are there in the US?
There are 16,567 Gastroenterology Physician providers across 54 states in the US. The average Gastroenterology Physician provider writes 833 Medicare Part D claims per year.
What drugs does LUIS ARMSTRONG, M.D. prescribe most often?
Based on 2023 Medicare Part D data, LUIS ARMSTRONG, M.D.'s most frequently prescribed drugs include Omeprazole, Famotidine, Pantoprazole Sodium. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does LUIS ARMSTRONG, M.D. accept Medicare?
LUIS ARMSTRONG, M.D. appears in CMS Medicare data with 1,552 Part D claims and 581 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify LUIS ARMSTRONG, M.D.'s credentials?
LUIS ARMSTRONG, M.D.'s NPI is 1952411670 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