2026 NPPES data Specialist NPI 1699952465 M.D.
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DARRIN FRIESEN, M.D.

Specialist in SAINT LOUIS, Missouri. 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
1K
Medicare Part D claims · 41 beneficiaries · Specialist avg: 1K
Generic prescribing
87%
generic claims · 13% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$710.83
39 payments · CMS Open Payments (Sunshine Act)
What the federal data reveals: DARRIN FRIESEN, M.D. is a Specialist ([object Object]) practicing in SAINT LOUIS, Missouri with a Medicare Part D prescribing footprint of 1K claims across 41 beneficiaries — 13% brand-name prescribing . Industry payments of $710.83 across 39 transactions are disclosed under CMS Open Payments (Sunshine Act).

What stands out: DARRIN FRIESEN, M.D. filed 1,004 Medicare Part D claims in 2023 across SAINT LOUIS, Missouri. Every figure on this page comes straight from federal CMS records, with no proprietary rating applied.

DARRIN FRIESEN, M.D. at a glance

Quality data not reported

NPI registry status

Active

Issued 01/23/2008

NPI 1699952465

Primary specialty

Specialist

High-volume

69,658 US NPIs in this specialty

Medicare Part D claims

1,004 32% vs specialty avg

2023 prescription claims

Specialty avg: 1,474

Specialty distribution in Missouri

How Specialist compares to other specialties among Missouri providers

Missouri providers

Specialist share within Missouri

1. Specialist42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Specialist share within Missouri

Specialty board-certification context

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

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

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

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

DARRIN FRIESEN, M.D. is a Specialist provider practicing in SAINT LOUIS, Missouri, according to the CMS National Plan and Provider Enumeration System (NPPES). Credentials: M.D.. NPI: 1699952465. 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.

DARRIN FRIESEN, M.D. appears in the CMS NPPES registry as a Specialist provider holding M.D. credentials at 1750 S BRENTWOOD BLVD, SAINT LOUIS, MO, 63144, with a listed phone of (314) 968-2111. NPI 1699952465 was issued on 01/23/2008. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what FRIESEN 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 1,004 prescription claims written by this provider, covering 41 Medicare beneficiaries and totaling roughly $199K in drug spend, split 13% brand-name and 87% 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.

Specialist is a high-volume specialty nationwide, with 69,658 enrolled providers across 55 states and an average of 1,474 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

1750 S BRENTWOOD BLVD
SAINT LOUIS, MO 63144

Provider Details

NPI 1699952465
Specialty Specialist
Credentials M.D.
Gender Male
NPI Issued 01/23/2008

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 DARRIN FRIESEN, M.D.. Source: openpaymentsdata.cms.gov.

Total received

$711

Largest payer

Corium, LLC

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 · Typical

DARRIN FRIESEN, M.D. — brand share 13.0%
Specialty average (est.)

13% brand-name claims vs 87% generic, on 1,004 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.

1,004
Total Claims
$199K
Total Drug Cost
41
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
1,417
Total Day Supply
42,256
Brand vs Generic
13% brand / 87% generic
Brand Drug Cost
$138K
Generic Drug Cost
$61K

Patient Demographics

Average Patient Age
44.9 years
Avg HCC Risk Score
0.73
Gender Split
44% female / 56% male
Age Distribution
<65: 30, 65-74: N/A, 75-84: N/A, 85+: 0

Top Prescribed Drugs (Medicare Part D)

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

Drug Claims
Lamotrigine
99
Ziprasidone Hcl
66
Fluoxetine Hcl
60
Dextroamphetamine-Amphet Er
Dextroamphetamine/Amphetamine
53
Trazodone Hcl
47
Escitalopram Oxalate
46
Sertraline Hcl
44
Aripiprazole
37
Quetiapine Fumarate Er
Quetiapine Fumarate
32
Bupropion Xl
Bupropion Hcl
31

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

Specialist Overview

How DARRIN FRIESEN, M.D. fits within the Specialist landscape nationally.

69,658
Specialist Providers in US
55
States with Specialist
1,474
Avg Claims per Provider

DARRIN FRIESEN, M.D.'s 1,004 claims are below the specialty average of 1,474.

Nearby Specialist Providers in Missouri

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

Compare Specialist nationally: see state-by-state distribution →

Frequently Asked Questions

What is DARRIN FRIESEN, M.D.'s specialty?
DARRIN FRIESEN, M.D. specializes in Specialist and practices in SAINT LOUIS, Missouri. Credentials: M.D..
How much does DARRIN FRIESEN, M.D. prescribe under Medicare Part D?
In 2023, DARRIN FRIESEN, M.D. wrote 1,004 Medicare Part D claims totaling $199K in drug costs for 41 beneficiaries.
Where is DARRIN FRIESEN, M.D. located?
DARRIN FRIESEN, M.D. is located at 1750 S BRENTWOOD BLVD, SAINT LOUIS, MO, 63144. Phone: (314) 968-2111.
What is DARRIN FRIESEN, M.D.'s NPI number?
DARRIN FRIESEN, M.D.'s National Provider Identifier (NPI) is 1699952465, issued on 01/23/2008.
Does DARRIN FRIESEN, M.D. prescribe more brand-name or generic drugs?
DARRIN FRIESEN, M.D.'s prescribing is 13% brand-name and 87% generic drugs by claim count, with $138K in brand drug costs.
How many Specialist providers are there in the US?
There are 69,658 Specialist providers across 55 states in the US. The average Specialist provider writes 1,474 Medicare Part D claims per year.
What drugs does DARRIN FRIESEN, M.D. prescribe most often?
Based on 2023 Medicare Part D data, DARRIN FRIESEN, M.D.'s most frequently prescribed drugs include Lamotrigine, Ziprasidone Hcl, Fluoxetine Hcl. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does DARRIN FRIESEN, M.D. accept Medicare?
DARRIN FRIESEN, M.D. appears in CMS Medicare data with 1,004 Part D claims and 41 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify DARRIN FRIESEN, M.D.'s credentials?
DARRIN FRIESEN, M.D.'s NPI is 1699952465 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