2026 NPPES data Psychiatric/Mental Health Nurse Practitioner NPI 1184806150 FNP
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MARY WILLIAMS, FNP

Psychiatric/Mental Health Nurse Practitioner in CLARKSDALE, Mississippi. 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
4K
Medicare Part D claims · 258 beneficiaries · Psychiatric/Mental Health Nurse Practitioner avg: 927
Generic prescribing
87%
generic claims · 13% brand-name · higher generic rates reduce patient out-of-pocket costs

What the federal data shows

MARY WILLIAMS, FNP filed 4,436 Medicare Part D claims in 2023 as a Psychiatric/Mental Health Nurse Practitioner in CLARKSDALE, Mississippi, prescribing 87% generic.

4K
Part D claims, 2023
87%
generic prescribing

Every figure on this page comes straight from federal CMS records (NPPES, Medicare Part D, MIPS, Open Payments) — no proprietary rating or editorial opinion is applied.

MARY WILLIAMS, FNP's Medicare Part D volume vs every U.S. prescriber

Total Medicare Part D claims, 2023 — across all CMS prescribers nationally

4,436 Top 7% higher than 93% of 1,370,886 prescribers

0–200: 670,926 prescribers (49%). Below this entry. 200–400: 182,923 prescribers (13%). Below this entry. 400–600: 90,619 prescribers (7%). Below this entry. 600–800: 56,224 prescribers (4%). Below this entry. 800–1,000: 40,919 prescribers (3%). Below this entry. 1,000–1,200: 31,827 prescribers (2%). Below this entry. 1,200–1,400: 26,224 prescribers (2%). Below this entry. 1,400–1,600: 21,710 prescribers (2%). Below this entry. 1,600–1,800: 19,072 prescribers (1%). Below this entry. 1,800–2,000: 16,451 prescribers (1%). Below this entry. 2,000–2,200: 213,991 prescribers (16%). This entry sits in this band. This provider 0 2K+ every Part D prescriber (claims/yr), bucketed by value

Each bar is a band; taller bars hold more prescribers. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.

Source CMS Medicare Part D Prescriber Public Use File · 2023

What does the federal data show about MARY WILLIAMS, FNP?

Quality data not reported

NPI registry status

Active

Issued 12/03/2007

NPI 1184806150

Primary specialty

Psychiatric/Mental Health Nurse Practitioner

Mid-sized

39,953 US NPIs in this specialty

Medicare Part D claims

4,436 379% vs specialty avg

2023 prescription claims

Specialty avg: 927

Specialty distribution in Mississippi

How Psychiatric/Mental Health Nurse Practitioner compares to other specialties among Mississippi providers

Mississippi providers

Psychiatric/Mental Health Nurse Practitioner share within Mississippi

1. Psychiatric/Mental Health Nurse Practitioner42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Psychiatric/Mental Health Nurse Practitioner share within Mississippi

Specialty board-certification context

Estimated specialty board-certified rate — Psychiatric/Mental Health Nurse Practitioner (ABMS / AOA reference)

Quality data not reported
Est. board-certified rate
78%
Psychiatric/Mental Health Nurse Practitioner ABMS/AOA estimate

Est. board-certified rate (Psychiatric/Mental Health Nurse Practitioner) — ABMS / AOA estimate

0%100%78%
Est. board-certified rate (Psychiatric/Mental Health Nurse Practitioner) — 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 WILLIAMS, FNP appears in the CMS NPPES registry as a Psychiatric/Mental Health Nurse Practitioner provider holding FNP credentials at 125 HIGHWAY 322, CLARKSDALE, MS, 38614, with a listed phone of (662) 351-1970. NPI 1184806150 was issued on 12/03/2007. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what WILLIAMS 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 4,436 prescription claims written by this provider, covering 258 Medicare beneficiaries and totaling roughly $358K in drug spend, split 13% brand-name and 87% generic by claim count, with an opioid prescribing rate of 0.4%. 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.

Psychiatric/Mental Health Nurse Practitioner is a mid-sized specialty nationwide, with 39,953 enrolled providers across 54 states and an average of 927 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

125 HIGHWAY 322
CLARKSDALE, MS 38614

Provider Details

NPI 1184806150
Specialty Psychiatric/Mental Health Nurse Practitioner
Credentials FNP
Gender Female
NPI Issued 12/03/2007

Brand vs generic prescribing mix · Typical

MARY WILLIAMS, FNP — brand share 13.0%
Specialty average (est.)

13% brand-name claims vs 87% generic, on 4,436 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.

4,436
Total Claims
$358K
Total Drug Cost
258
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
7,080
Total Day Supply
207,109
Brand vs Generic
13% brand / 87% generic
Brand Drug Cost
$306K
Generic Drug Cost
$48K
Opioid Claims
16 (0.4% rate)
Antibiotic Claims
95

Patient Demographics

Average Patient Age
68.4 years
Avg HCC Risk Score
1.60
Gender Split
68% female / 32% male
Age Distribution
<65: 70, 65-74: 128, 75-84: 44, 85+: 16

Top Prescribed Drugs (Medicare Part D)

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

What MARY WILLIAMS, FNP prescribes most

Top Medicare Part D drugs by claim count, 2023

claims
Source CMS Medicare Part D Prescriber Public Use File As of 2023
Drug Claims
Amlodipine Besylate
326
Metformin Hcl
187
Atorvastatin Calcium
164
Gabapentin
154
Losartan Potassium
147
Levothyroxine Sodium
137
Pantoprazole Sodium
123
Furosemide
121
Montelukast Sodium
107
Omeprazole
102

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

Psychiatric/Mental Health Nurse Practitioner Overview

How MARY WILLIAMS, FNP fits within the Psychiatric/Mental Health Nurse Practitioner landscape nationally.

39,953
Psychiatric/Mental Health Nurse Practitioner Providers in US
54
States with Psychiatric/Mental Health Nurse Practitioner
927
Avg Claims per Provider

MARY WILLIAMS, FNP's 4,436 claims are above the specialty average of 927.

Nearby Psychiatric/Mental Health Nurse Practitioner Providers in Mississippi

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

Compare Psychiatric/Mental Health Nurse Practitioner nationally: see state-by-state distribution →

Frequently Asked Questions

What is MARY WILLIAMS, FNP's specialty?
MARY WILLIAMS, FNP specializes in Psychiatric/Mental Health Nurse Practitioner and practices in CLARKSDALE, Mississippi. Credentials: FNP.
How much does MARY WILLIAMS, FNP prescribe under Medicare Part D?
In 2023, MARY WILLIAMS, FNP wrote 4,436 Medicare Part D claims totaling $358K in drug costs for 258 beneficiaries.
Where is MARY WILLIAMS, FNP located?
MARY WILLIAMS, FNP is located at 125 HIGHWAY 322, CLARKSDALE, MS, 38614. Phone: (662) 351-1970.
What is MARY WILLIAMS, FNP's NPI number?
MARY WILLIAMS, FNP's National Provider Identifier (NPI) is 1184806150, issued on 12/03/2007.
Does MARY WILLIAMS, FNP prescribe more brand-name or generic drugs?
MARY WILLIAMS, FNP's prescribing is 13% brand-name and 87% generic drugs by claim count, with $306K in brand drug costs.
Does MARY WILLIAMS, FNP prescribe opioids?
Yes, MARY WILLIAMS, FNP had 16 opioid claims in 2023 with an opioid prescribing rate of 0.4%.
How many Psychiatric/Mental Health Nurse Practitioner providers are there in the US?
There are 39,953 Psychiatric/Mental Health Nurse Practitioner providers across 54 states in the US. The average Psychiatric/Mental Health Nurse Practitioner provider writes 927 Medicare Part D claims per year.
What drugs does MARY WILLIAMS, FNP prescribe most often?
Based on 2023 Medicare Part D data, MARY WILLIAMS, FNP's most frequently prescribed drugs include Amlodipine Besylate, Metformin Hcl, Atorvastatin Calcium. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does MARY WILLIAMS, FNP accept Medicare?
MARY WILLIAMS, FNP appears in CMS Medicare data with 4,436 Part D claims and 258 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify MARY WILLIAMS, FNP's credentials?
MARY WILLIAMS, FNP's NPI is 1184806150 with credentials FNP. 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