2026 NPPES data Neurology Physician NPI 1235133265 D.O.
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MARY CHIASSON, D.O.

Neurology Physician in BLOOMINGTON, Minnesota. 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 · 250 beneficiaries · Neurology Physician avg: 1K
Generic prescribing
82%
generic claims · 18% brand-name · higher generic rates reduce patient out-of-pocket costs
What the federal data reveals: MARY CHIASSON, D.O. is a Neurology Physician ([object Object]) practicing in BLOOMINGTON, Minnesota with a Medicare Part D prescribing footprint of 2K claims across 250 beneficiaries — 18% brand-name prescribing .

What stands out: MARY CHIASSON, D.O. filed 2,093 Medicare Part D claims in 2023 across BLOOMINGTON, Minnesota. Every figure on this page comes straight from federal CMS records, with no proprietary rating applied.

Board-eligible specialty (heuristic — not verified)

MARY CHIASSON, D.O. practices in an ABMS-board-eligible specialty but we don't have enough CMS-participation signals to confirm active board-certified status. Consult CertificationMatters.org (the official ABMS public lookup).

MARY CHIASSON, D.O. at a glance

Quality data not reported

NPI registry status

Active

Issued 06/08/2005

NPI 1235133265

Primary specialty

Neurology Physician

Mid-sized

19,866 US NPIs in this specialty

Medicare Part D claims

2,093 60% vs specialty avg

2023 prescription claims

Specialty avg: 1,309

Specialty distribution in Minnesota

How Neurology Physician compares to other specialties among Minnesota providers

Minnesota providers

Neurology Physician share within Minnesota

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

Specialty board-certification context

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

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

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

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

MARY CHIASSON, D.O. is a Neurology Physician provider practicing in BLOOMINGTON, Minnesota, according to the CMS National Plan and Provider Enumeration System (NPPES). Credentials: D.O.. NPI: 1235133265. 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.

MARY CHIASSON, D.O. appears in the CMS NPPES registry as a Neurology Physician provider holding D.O. credentials at 3601 MINNESOTA DR STE 200, BLOOMINGTON, MN, 55435, with a listed phone of (612) 879-1000. NPI 1235133265 was issued on 06/08/2005. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what CHIASSON 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 2,093 prescription claims written by this provider, covering 250 Medicare beneficiaries and totaling roughly $464K in drug spend, split 18% brand-name and 82% 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.

Neurology Physician is a mid-sized specialty nationwide, with 19,866 enrolled providers across 54 states and an average of 1,309 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

3601 MINNESOTA DR STE 200
BLOOMINGTON, MN 55435

Provider Details

NPI 1235133265
Specialty Neurology Physician
Credentials D.O.
Gender Female
NPI Issued 06/08/2005

Brand vs generic prescribing mix · Typical

MARY CHIASSON, D.O. — brand share 18.0%
Specialty average (est.)

18% brand-name claims vs 82% generic, on 2,093 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.

2,093
Total Claims
$464K
Total Drug Cost
250
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
3,065
Total Day Supply
86,606
Brand vs Generic
18% brand / 82% generic
Brand Drug Cost
$372K
Generic Drug Cost
$92K

Patient Demographics

Average Patient Age
71.0 years
Avg HCC Risk Score
1.02
Gender Split
72% female / 28% male
Age Distribution
<65: 39, 65-74: 115, 75-84: 77, 85+: 19

Top Prescribed Drugs (Medicare Part D)

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

Drug Claims
Sumatriptan Succinate
282
Gabapentin
150
Rizatriptan
Rizatriptan Benzoate
110
Tizanidine Hcl
104
Donepezil Hcl
86
Ubrelvy
Ubrogepant
84
Carbidopa-Levodopa
Carbidopa/Levodopa
75
Aimovig Autoinjector
Erenumab-Aooe
67
Levetiracetam
64
Emgality Pen
Galcanezumab-Gnlm
60

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

Neurology Physician Overview

How MARY CHIASSON, D.O. fits within the Neurology Physician landscape nationally.

19,866
Neurology Physician Providers in US
54
States with Neurology Physician
1,309
Avg Claims per Provider

MARY CHIASSON, D.O.'s 2,093 claims are above the specialty average of 1,309.

Nearby Neurology Physician Providers in Minnesota

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

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

Frequently Asked Questions

What is MARY CHIASSON, D.O.'s specialty?
MARY CHIASSON, D.O. specializes in Neurology Physician and practices in BLOOMINGTON, Minnesota. Credentials: D.O..
How much does MARY CHIASSON, D.O. prescribe under Medicare Part D?
In 2023, MARY CHIASSON, D.O. wrote 2,093 Medicare Part D claims totaling $464K in drug costs for 250 beneficiaries.
Where is MARY CHIASSON, D.O. located?
MARY CHIASSON, D.O. is located at 3601 MINNESOTA DR STE 200, BLOOMINGTON, MN, 55435. Phone: (612) 879-1000.
What is MARY CHIASSON, D.O.'s NPI number?
MARY CHIASSON, D.O.'s National Provider Identifier (NPI) is 1235133265, issued on 06/08/2005.
Does MARY CHIASSON, D.O. prescribe more brand-name or generic drugs?
MARY CHIASSON, D.O.'s prescribing is 18% brand-name and 82% generic drugs by claim count, with $372K in brand drug costs.
How many Neurology Physician providers are there in the US?
There are 19,866 Neurology Physician providers across 54 states in the US. The average Neurology Physician provider writes 1,309 Medicare Part D claims per year.
What drugs does MARY CHIASSON, D.O. prescribe most often?
Based on 2023 Medicare Part D data, MARY CHIASSON, D.O.'s most frequently prescribed drugs include Sumatriptan Succinate, Gabapentin, Rizatriptan. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does MARY CHIASSON, D.O. accept Medicare?
MARY CHIASSON, D.O. appears in CMS Medicare data with 2,093 Part D claims and 250 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify MARY CHIASSON, D.O.'s credentials?
MARY CHIASSON, D.O.'s NPI is 1235133265 with credentials D.O.. 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