Doctor profile · Federal record

Dr. Norman Nishioka, MD

Gastroenterology Physician (CMS: Gastroenterology) · Internal Medicine Physician · Boston, MA

  • NPI 1174513600
  • Accepts Medicare
  • 45 yrs in practice
  • Male
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
55 Fruit St, Gastroenterology Associates Blk 4
Boston, MA 021142621
(617) 726-4422
fax (617) 724-6832
Mailing address
Po Box 9142, Mass General Physician Organization
Charlestown, MA 021299142

Credentials & registration

NPPES · NUCC
NPI registered
October 2005 — 21 yrs on file
Profile last updated
September 11, 2025
Year of graduation
1981 — 45 yrs since
Specialty taxonomy
207RG0100X — NUCC code
State license (1)
Massachusetts #51195
Medicaid
MA #3024822

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1174513600. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
1,779
Distinct HCPCS
10
Medicare allowed
$206,767
HCPCS Description Services Patients Avg allowed
G0500 Moderate sedation services provided by the same physician or other qualified health care professional performing a gastrointestinal endoscopic service that sedation supports, requiring the presence of an independent trained observer to assist in the monito 580 574 $6
45385 Removal of polyps or growths of large bowel using an endoscope with mechanical snare 446 445 $268
45380 Biopsy of large bowel using a flexible endoscope 196 196 $38
43239 Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope 195 193 $115
99214 Established patient office or other outpatient visit, 30-39 minutes 89 73 $104
43270 Destruction of polyp or growth of esophagus, stomach, and/or upper small bowel using a flexible endoscope 66 43 $230
G0105 Colorectal cancer screening; colonoscopy on individual at high risk 53 53 $195
99215 Established patient office or other outpatient visit, 40-54 minutes 40 40 $153
99231 Subsequent hospital care with straightforward or low level of medical decision making, per day, if using time, at least 25 minutes 26 18 $53
99443 Telephone medical discussion with physician, 21-30 minutes 22 18 $103

In context: peer comparison

Among 78 peers in Boston Gastroenterology Physician, average services per provider: 56. This provider delivers 32× the peer median.

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
542
Patients
412
Total drug cost
$15,553
Drug Type Claims Patients Total cost
Gavilyte-G (Peg3350/Sod Sulf,Bicarb,Cl/Kcl) Brand 313 310 $4,709
Omeprazole Generic 147 53 $7,665
Peg 3350-Electrolyte (Sodium Chloride/Nahco3/Kcl/Peg) Brand 20 20 $432
Pantoprazole Sodium Generic 18 0 $875
Peg-3350 and Electrolytes (Peg3350/Sod Sulf,Bicarb,Cl/Kcl) Brand 17 17 $289
Esomeprazole Magnesium Generic 15 0 $712
Sod Sulf-Potass Sulf-Mag Sulf (Sodium, Potassium,Mag Sulfates) Brand 12 12 $870

Frequently asked questions

Auto-generated from federal data
What is Dr. Norman Nishioka's medical specialty?
Dr. Norman Nishioka practices Gastroenterology Physician in Boston, MA.
Where does Dr. Norman Nishioka practice?
Dr. Norman Nishioka practices at 55 Fruit St, Boston, MA 021142621. Office phone: 6177264422.
What is Dr. Norman Nishioka's NPI?
Dr. Norman Nishioka's National Provider Identifier (NPI) is 1174513600, issued by NPPES.
Does Dr. Norman Nishioka accept Medicare assignment?
Yes. Dr. Norman Nishioka accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Norman Nishioka commonly perform?
Top Medicare-reported procedures in 2023: Moderate sedation services provided by the same physician or other qualified health care professional performing a gastrointestinal endoscopic service that sedation supports, requiring the presence of an independent trained observer to assist in the monito (HCPCS G0500); Removal of polyps or growths of large bowel using an endoscope with mechanical snare (HCPCS 45385); Biopsy of large bowel using a flexible endoscope (HCPCS 45380). Source: CMS Medicare Physician & Other Practitioners file.