2026 NPPES data Internal Medicine Physician NPI 1124130695 MD
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STEVEN GERSTNER, MD

Internal Medicine Physician in BILLINGS, Montana. 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
5K
Medicare Part D claims · 429 beneficiaries · Internal Medicine Physician avg: 3K
Generic prescribing
88%
generic claims · 12% brand-name · higher generic rates reduce patient out-of-pocket costs
What the federal data reveals: STEVEN GERSTNER, MD is a Internal Medicine Physician ([object Object]) practicing in BILLINGS, Montana with a Medicare Part D prescribing footprint of 5K claims across 429 beneficiaries — 12% brand-name prescribing .

What stands out: STEVEN GERSTNER, MD filed 4,554 Medicare Part D claims in 2023 across BILLINGS, Montana. Every figure on this page comes straight from federal CMS records, with no proprietary rating applied.

Board certification likely (heuristic — not verified)

STEVEN GERSTNER, 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).

STEVEN GERSTNER, MD at a glance

Quality data not reported

NPI registry status

Active

Issued 08/31/2006

NPI 1124130695

Primary specialty

Internal Medicine Physician

High-volume

172,858 US NPIs in this specialty

Medicare Part D claims

4,554 68% vs specialty avg

2023 prescription claims

Specialty avg: 2,716

Specialty distribution in Montana

How Internal Medicine Physician compares to other specialties among Montana providers

Montana providers

Internal Medicine Physician share within Montana

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

Specialty board-certification context

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

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

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

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

STEVEN GERSTNER, MD is a Internal Medicine Physician provider practicing in BILLINGS, Montana, according to the CMS National Plan and Provider Enumeration System (NPPES). Credentials: MD. NPI: 1124130695. 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.

STEVEN GERSTNER, MD appears in the CMS NPPES registry as a Internal Medicine Physician provider holding MD credentials at 801 N 29TH ST, BILLINGS, MT, 59101, with a listed phone of (406) 238-2500. NPI 1124130695 was issued on 08/31/2006. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what GERSTNER 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 4,554 prescription claims written by this provider, covering 429 Medicare beneficiaries and totaling roughly $483K in drug spend, split 12% brand-name and 88% generic by claim count, with an opioid prescribing rate of 6.6%. 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.

Internal Medicine Physician is a high-volume specialty nationwide, with 172,858 enrolled providers across 56 states and an average of 2,716 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

801 N 29TH ST
BILLINGS, MT 59101

Provider Details

NPI 1124130695
Specialty Internal Medicine Physician
Credentials MD
Gender Male
NPI Issued 08/31/2006

Hospital and facility affiliations

Facilities where STEVEN GERSTNER, 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.

BILLINGS CLINIC
★★★★☆ 4/5
BILLINGS, MT
Acute Care Hospitals
CMS CCN: 270004

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

Brand vs generic prescribing mix · Typical

STEVEN GERSTNER, MD — brand share 12.0%
Specialty average (est.)

12% brand-name claims vs 88% generic, on 4,554 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.

4,554
Total Claims
$483K
Total Drug Cost
429
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
10,723
Total Day Supply
312,367
Brand vs Generic
12% brand / 88% generic
Brand Drug Cost
$399K
Generic Drug Cost
$82K
Opioid Claims
301 (6.6% rate)
Antibiotic Claims
56

Patient Demographics

Average Patient Age
74.4 years
Avg HCC Risk Score
1.24
Gender Split
48% female / 52% male
Age Distribution
<65: 31, 65-74: 182, 75-84: 171, 85+: 45

Top Prescribed Drugs (Medicare Part D)

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

Drug Claims
Atorvastatin Calcium
204
Lisinopril
203
Levothyroxine Sodium
202
Rosuvastatin Calcium
198
Omeprazole
191
Losartan Potassium
183
Hydrocodone-Acetaminophen
Hydrocodone/Acetaminophen
144
Hydrochlorothiazide
134
Gabapentin
101
Tamsulosin Hcl
99

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

Internal Medicine Physician Overview

How STEVEN GERSTNER, MD fits within the Internal Medicine Physician landscape nationally.

172,858
Internal Medicine Physician Providers in US
56
States with Internal Medicine Physician
2,716
Avg Claims per Provider

STEVEN GERSTNER, MD's 4,554 claims are above the specialty average of 2,716.

Nearby Internal Medicine Physician Providers in Montana

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

Compare Internal Medicine Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is STEVEN GERSTNER, MD's specialty?
STEVEN GERSTNER, MD specializes in Internal Medicine Physician and practices in BILLINGS, Montana. Credentials: MD.
How much does STEVEN GERSTNER, MD prescribe under Medicare Part D?
In 2023, STEVEN GERSTNER, MD wrote 4,554 Medicare Part D claims totaling $483K in drug costs for 429 beneficiaries.
Where is STEVEN GERSTNER, MD located?
STEVEN GERSTNER, MD is located at 801 N 29TH ST, BILLINGS, MT, 59101. Phone: (406) 238-2500.
What is STEVEN GERSTNER, MD's NPI number?
STEVEN GERSTNER, MD's National Provider Identifier (NPI) is 1124130695, issued on 08/31/2006.
Does STEVEN GERSTNER, MD prescribe more brand-name or generic drugs?
STEVEN GERSTNER, MD's prescribing is 12% brand-name and 88% generic drugs by claim count, with $399K in brand drug costs.
Does STEVEN GERSTNER, MD prescribe opioids?
Yes, STEVEN GERSTNER, MD had 301 opioid claims in 2023 with an opioid prescribing rate of 6.6%.
How many Internal Medicine Physician providers are there in the US?
There are 172,858 Internal Medicine Physician providers across 56 states in the US. The average Internal Medicine Physician provider writes 2,716 Medicare Part D claims per year.
What drugs does STEVEN GERSTNER, MD prescribe most often?
Based on 2023 Medicare Part D data, STEVEN GERSTNER, MD's most frequently prescribed drugs include Atorvastatin Calcium, Lisinopril, Levothyroxine Sodium. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does STEVEN GERSTNER, MD accept Medicare?
STEVEN GERSTNER, MD appears in CMS Medicare data with 4,554 Part D claims and 429 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify STEVEN GERSTNER, MD's credentials?
STEVEN GERSTNER, MD's NPI is 1124130695 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