Doctor profile · Federal record

Dr. Thomas McMahon, MD

Gastroenterology Physician (CMS: Gastroenterology) · Gastroenterology Physician · Wareham, MA

  • NPI 1619048030
  • Accepts Medicare
  • 46 yrs in practice
  • Licensed in 2 states
  • Male
  • Group practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
100 Rosebrook Way
Wareham, MA 025711138
(508) 973-4974
fax (508) 273-4954
Mailing address
200 Mill RD
Fairhaven, MA 027195252

Credentials & registration

NPPES · NUCC
NPI registered
November 2006 — 20 yrs on file
Profile last updated
February 2, 2026
Year of graduation
1980 — 46 yrs since
Specialty taxonomy
207RG0100X — NUCC code
State licenses (2)
Massachusetts #50774 · Rhode Island #6825

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1619048030. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
114
Distinct HCPCS
6
Medicare allowed
$15,156
HCPCS Description Services Patients Avg allowed
99214 Established patient office or other outpatient visit, 30-39 minutes 28 23 $123
43239 Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope 26 26 $113
99213 Established patient office or other outpatient visit, 20-29 minutes 23 22 $93
45385 Removal of polyps or growths of large bowel using an endoscope with mechanical snare 13 13 $240
45380 Biopsy of large bowel using a flexible endoscope 12 12 $109
G0105 Colorectal cancer screening; colonoscopy on individual at high risk 12 12 $184

In context: peer comparison

Among 1 peers in Wareham Gastroenterology Physician, average services per provider: 19. This provider delivers 6.0× the peer median.

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
536
Patients
134
Total drug cost
$201,445
Drug Type Claims Patients Total cost
Omeprazole Generic 195 80 $3,285
Pantoprazole Sodium Generic 101 38 $2,061
Colestipol Hcl Generic 40 16 $2,734
Linzess (Linaclotide) Brand 39 0 $23,580
Esomeprazole Magnesium Generic 26 0 $2,167
Mesalamine Generic 26 0 $20,193
Dicyclomine Hcl Generic 25 0 $1,133
Dexlansoprazole Dr (Dexlansoprazole) Brand 24 0 $10,603
Azathioprine Generic 13 0 $1,170
Humira(Cf) Pen (Adalimumab) Brand 13 0 $128,179

Frequently asked questions

Auto-generated from federal data
What is Dr. Thomas McMahon's medical specialty?
Dr. Thomas McMahon practices Gastroenterology Physician in Wareham, MA.
Where does Dr. Thomas McMahon practice?
Dr. Thomas McMahon practices at 100 Rosebrook Way, Wareham, MA 025711138. Office phone: 5089734974.
What is Dr. Thomas McMahon's NPI?
Dr. Thomas McMahon's National Provider Identifier (NPI) is 1619048030, issued by NPPES.
Does Dr. Thomas McMahon accept Medicare assignment?
Yes. Dr. Thomas McMahon accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Thomas McMahon commonly perform?
Top Medicare-reported procedures in 2023: Established patient office or other outpatient visit (HCPCS 99214); Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (HCPCS 43239); Established patient office or other outpatient visit (HCPCS 99213). Source: CMS Medicare Physician & Other Practitioners file.