2026 NPPES data Psychiatry Physician NPI 1922052836 M.D.
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GREGORY SINGLETON, M.D.

Psychiatry Physician in LOUISVILLE, Kentucky. 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
678
Medicare Part D claims · 39 beneficiaries · Psychiatry Physician avg: 1K
Generic prescribing
97%
generic claims · 3% brand-name · higher generic rates reduce patient out-of-pocket costs

What the federal data shows

GREGORY SINGLETON, M.D. filed 678 Medicare Part D claims in 2023 as a Psychiatry Physician in LOUISVILLE, Kentucky, prescribing 97% generic.

678
Part D claims, 2023
97%
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.

GREGORY SINGLETON, M.D.'s Medicare Part D volume vs every U.S. prescriber

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

678 Top 31% higher than 69% 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%). This entry sits in this band. 800–1,000: 40,919 prescribers (3%). Above this entry. 1,000–1,200: 31,827 prescribers (2%). Above this entry. 1,200–1,400: 26,224 prescribers (2%). Above this entry. 1,400–1,600: 21,710 prescribers (2%). Above this entry. 1,600–1,800: 19,072 prescribers (1%). Above this entry. 1,800–2,000: 16,451 prescribers (1%). Above this entry. 2,000–2,200: 213,991 prescribers (16%). Above this entry. 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

Board-eligible specialty (heuristic — not verified)

GREGORY SINGLETON, M.D. 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).

What does the federal data show about GREGORY SINGLETON, M.D.?

Quality data not reported

NPI registry status

Active

Issued 05/22/2006

NPI 1922052836

Primary specialty

Psychiatry Physician

High-volume

53,104 US NPIs in this specialty

Medicare Part D claims

678 35% vs specialty avg

2023 prescription claims

Specialty avg: 1,038

Specialty distribution in Kentucky

How Psychiatry Physician compares to other specialties among Kentucky providers

Kentucky providers

Psychiatry Physician share within Kentucky

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

Specialty board-certification context

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

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

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

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

GREGORY SINGLETON, M.D. appears in the CMS NPPES registry as a Psychiatry Physician provider holding M.D. credentials at 401 E CHESTNUT ST, LOUISVILLE, KY, 40202, with a listed phone of (502) 813-6627. NPI 1922052836 was issued on 05/22/2006. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what SINGLETON 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 678 prescription claims written by this provider, covering 39 Medicare beneficiaries and totaling roughly $49K in drug spend, split 3% brand-name and 97% 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.

Psychiatry Physician is a high-volume specialty nationwide, with 53,104 enrolled providers across 56 states and an average of 1,038 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

401 E CHESTNUT ST
LOUISVILLE, KY 40202

Provider Details

NPI 1922052836
Specialty Psychiatry Physician
Credentials M.D.
Gender Male
NPI Issued 05/22/2006

Brand vs generic prescribing mix · Generic-heavy

GREGORY SINGLETON, M.D. — brand share 3.0%
Specialty average (est.)

3% brand-name claims vs 97% generic, on 678 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.

678
Total Claims
$49K
Total Drug Cost
39
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
1,135
Total Day Supply
33,894
Brand vs Generic
3% brand / 97% generic
Brand Drug Cost
$18K
Generic Drug Cost
$31K

Patient Demographics

Average Patient Age
62.1 years
Avg HCC Risk Score
1.01
Gender Split
49% female / 51% male
Age Distribution
<65: 17, 65-74: 17, 75-84: N/A, 85+: N/A

Top Prescribed Drugs (Medicare Part D)

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

What GREGORY SINGLETON, M.D. 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
Alprazolam
59
Quetiapine Fumarate
52
Duloxetine Hcl
50
Diazepam
38
Zolpidem Tartrate
30
Clonazepam
27
Trazodone Hcl
27
Gabapentin
25
Temazepam
24
Divalproex Sodium
21

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

Psychiatry Physician Overview

How GREGORY SINGLETON, M.D. fits within the Psychiatry Physician landscape nationally.

53,104
Psychiatry Physician Providers in US
56
States with Psychiatry Physician
1,038
Avg Claims per Provider

GREGORY SINGLETON, M.D.'s 678 claims are below the specialty average of 1,038.

Nearby Psychiatry Physician Providers in Kentucky

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

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

Frequently Asked Questions

What is GREGORY SINGLETON, M.D.'s specialty?
GREGORY SINGLETON, M.D. specializes in Psychiatry Physician and practices in LOUISVILLE, Kentucky. Credentials: M.D..
How much does GREGORY SINGLETON, M.D. prescribe under Medicare Part D?
In 2023, GREGORY SINGLETON, M.D. wrote 678 Medicare Part D claims totaling $49K in drug costs for 39 beneficiaries.
Where is GREGORY SINGLETON, M.D. located?
GREGORY SINGLETON, M.D. is located at 401 E CHESTNUT ST, LOUISVILLE, KY, 40202. Phone: (502) 813-6627.
What is GREGORY SINGLETON, M.D.'s NPI number?
GREGORY SINGLETON, M.D.'s National Provider Identifier (NPI) is 1922052836, issued on 05/22/2006.
Does GREGORY SINGLETON, M.D. prescribe more brand-name or generic drugs?
GREGORY SINGLETON, M.D.'s prescribing is 3% brand-name and 97% generic drugs by claim count, with $18K in brand drug costs.
How many Psychiatry Physician providers are there in the US?
There are 53,104 Psychiatry Physician providers across 56 states in the US. The average Psychiatry Physician provider writes 1,038 Medicare Part D claims per year.
What drugs does GREGORY SINGLETON, M.D. prescribe most often?
Based on 2023 Medicare Part D data, GREGORY SINGLETON, M.D.'s most frequently prescribed drugs include Alprazolam, Quetiapine Fumarate, Duloxetine Hcl. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does GREGORY SINGLETON, M.D. accept Medicare?
GREGORY SINGLETON, M.D. appears in CMS Medicare data with 678 Part D claims and 39 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify GREGORY SINGLETON, M.D.'s credentials?
GREGORY SINGLETON, M.D.'s NPI is 1922052836 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