Doctor profile · Federal record

Dr. Brian Karaszewski, M.D.

Internal Medicine Physician (CMS: Internal Medicine) · Williamsville, NY

  • NPI 1255478376
  • Accepts Medicare
  • 29 yrs in practice
  • Male
  • Solo practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
400 International Dr.
Williamsville, NY 14221
(716) 631-3555
fax (716) 631-9525

Credentials & registration

NPPES · NUCC
NPI registered
January 2007 — 19 yrs on file
Profile last updated
August 19, 2019
Year of graduation
1997 — 29 yrs since
Specialty taxonomy
207R00000X — NUCC code
State license (1)
New York #213340-1

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1255478376. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
487
Distinct HCPCS
8
Medicare allowed
$39,202
HCPCS Description Services Patients Avg allowed
99213 Established patient office or other outpatient visit, 20-29 minutes 177 125 $86
G0439 Annual wellness visit, includes a personalized prevention plan of service (pps), subsequent visit 123 123 $123
99457 Management using the results of remote vital sign monitoring per calendar month, first 20 minutes 86 25 $46
99454 Remote monitoring of physiologic parameters, initial supply of devices with daily recordings or programmed alerts transmission, each 30 days 48 17 $47
99211 Office or other outpatient visit for the evaluation and management of established patient that may not require presence of healthcare professional 15 11 $22
96132 Evaluation of neuropsychological test, first hour 13 13 $125
96138 Administration of psychological or neuropsychological test by technician, first 30 minutes 13 13 $32
99453 Remote monitoring of physiologic parameters, initial set-up and patient education on use of equipment 12 12 $18

In context: peer comparison

Among 18 peers in Williamsville Internal Medicine Physician, average services per provider: 65. This provider delivers 7.5× the peer median.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$4,110
Transactions
190
Manufacturers
15
Payer (manufacturer) Industry Txns Amount
Abbvie INC. 40 $755.13
AstraZeneca Pharmaceuticals Lp 6 $422.11
Lilly USA, LLC 26 $390.41
GlaxoSmithKline, LLC. 22 $371.86
Amgen INC. 18 $344.87
Boehringer Ingelheim Pharmaceuticals, INC. 14 $309.12
BioCryst US Sales Co., LLC 11 $211.07
Novo Nordisk INC 11 $201.04
Takeda Pharmaceuticals U.S.A., INC. 20 $164.51
Exact Sciences Corporation 6 $130.87
Zoll Services LLC (A/K/A Zoll LifeCor Corp) 1 $90.66
Janssen Biotech, INC. 4 $86.73
Ucb, INC. 3 $75.85
Mylan Specialty L.P. 4 $61.93
Astellas Pharma US INC 4 $59.73

By nature of payment

Food and Beverage
$4,110

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
5,246
Patients
1,350
Total drug cost
$101,642
Drug Type Claims Patients Total cost
Levothyroxine Sodium Generic 920 236 $21,897
Amlodipine Besylate Generic 583 136 $4,905
Rosuvastatin Calcium Generic 491 141 $11,385
Atorvastatin Calcium Generic 450 130 $8,254
Omeprazole Generic 397 94 $4,778
Lisinopril Generic 395 101 $4,652
Metoprolol Succinate Generic 331 82 $8,775
Pantoprazole Sodium Generic 309 85 $6,757
Furosemide Generic 227 63 $1,661
Metformin Hcl Generic 216 60 $3,267

Hospital affiliations

CMS Hospital Compare

Frequently asked questions

Auto-generated from federal data
What is Dr. Brian Karaszewski's medical specialty?
Dr. Brian Karaszewski practices Internal Medicine Physician in Williamsville, NY.
Where does Dr. Brian Karaszewski practice?
Dr. Brian Karaszewski practices at 400 International Dr., Williamsville, NY 14221. Office phone: 7166313555.
What is Dr. Brian Karaszewski's NPI?
Dr. Brian Karaszewski's National Provider Identifier (NPI) is 1255478376, issued by NPPES.
Does Dr. Brian Karaszewski accept Medicare assignment?
Yes. Dr. Brian Karaszewski accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Brian Karaszewski commonly perform?
Top Medicare-reported procedures in 2023: Established patient office or other outpatient visit (HCPCS 99213); Annual wellness visit, includes a personalized prevention plan of service (pps), subsequent visit (HCPCS G0439); Management using the results of remote vital sign monitoring per calendar month (HCPCS 99457). Source: CMS Medicare Physician & Other Practitioners file.