Recently Updated NPI Information — some details in this NPI profile have been updated in the NPI registry within the last 60 days.

DR. NORMAN SHIZUAKI NISHIOKA MD
NPI 1174513600
Internal Medicine - Gastroenterology in Boston, MA

Active since October 26, 2005PECOS EnrolledAccepts Medicare Assignment
55 FRUIT ST, GASTROENTEROLOGY ASSOCIATES BLK 4, BOSTON, MA 02114(617) 726-4422(617) 724-6832 Get Directions Write a Review

NPPES record last updated: July 13, 2026. Verified against the NPPES registry weekly; last sync: August 16, 2026.

Record update history: Jul 13, 2026, Sep 11, 2025 (2 updates tracked since 2025).

About Dr. Norman Shizuaki Nishioka Md NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

DR. NORMAN SHIZUAKI NISHIOKA MD (NPI 1174513600) is an individual gastroenterology provider in Boston, Massachusetts, licensed in Massachusetts (51195) and active in the NPI registry since October 2005. He is enrolled in Medicare PECOS, is affiliated with Massachusetts General Hospital, and is a graduate of University Of California, Geffen School Of Medicine (1981).

NPPES Registry Identity

NPI1174513600
Entity TypeIndividualMale
Primary Taxonomy207RG0100X
Provider Legal NameDR. NORMAN SHIZUAKI NISHIOKACredential: MD
Location Address55 FRUIT ST, GASTROENTEROLOGY ASSOCIATES BLK 4Boston, MA 02114-2621
Mailing AddressPo Box 9142, Mass General Physician OrganizationCharlestown, MA 02129-9142 · (617) 724-0287 · Fax (617) 726-2894
Fax(617) 724-6832
Sole ProprietorNo
Medical School CMSUniversity Of California, Geffen School Of MedicineGraduated 1981
Enumeration DateOctober 26, 2005
Last NPPES UpdateJuly 13, 20262 updates tracked since enumeration
NPI 1174513600 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

Primary SpecialtyInternal Medicine · GastroenterologyAllopathic & Osteopathic Physicians
Taxonomy Code207RG0100X
License Licensed in MA · 51195
Definition
An internist who specializes in diagnosis and treatment of diseases of the digestive organs including the stomach, bowels, liver and gallbladder. This specialist treats conditions such as abdominal pain, ulcers, diarrhea, cancer and jaundice and performs complex diagnostic and therapeutic procedures using endoscopes to visualize internal organs.
Also ListedInternal MedicineTaxonomy 207R00000X · License 51195 (MA)
55 FRUIT ST, Boston, MA 02114

Other Identifiers 3

Other051195MA · Tufts Health Plan
OtherJ04630MA · Bcbs Ma
Medicaid3024822MA

Accepted Insurance

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

Enrolled in Medicare and accepts Medicare assignment

Dr. Norman Shizuaki Nishioka Md is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID2567447915
PECOS Enrollment IDI20040621001345
Eligible to Order & Refer Part B Labs & Imaging Durable Medical Equipment Home Health Agency Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Areas of Expertise CMS Part B claims 16

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

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 G0500
Moderate sedation is a method where a physician uses medication to help you relax during a gastrointestinal endoscopy. An independent trained observer will be present to monitor your vital signs and ensure your safety throughout the procedure. It's a common and safe practice.
440 services433 patients
Removal of polyps or growths of large bowel using an endoscope with mechanical snare 45385
This procedure involves using a thin, flexible tube called an endoscope to examine the large bowel. If any abnormal growths or polyps are found, a tool called a mechanical snare is used to remove them. This is a common method to prevent potential health issues.
338 services336 patients
Biopsy of large bowel using a flexible endoscope 45380
A biopsy of the large bowel using a flexible endoscope is a procedure where a thin, flexible tube with a camera is inserted through the rectum to examine the bowel. If abnormal tissue is found, a small sample is taken for further examination. This helps in diagnosing conditions like inflammation, polyps, or cancer.
178 services177 patients
Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope 43239
This procedure involves using a thin, flexible tube with a light and camera, known as an endoscope, to examine the esophagus, stomach, and upper part of the small intestine. Small tissue samples are taken for further examination to help diagnose various conditions.
170 services168 patients
Destruction of polyp or growth of esophagus, stomach, and/or upper small bowel using a flexible endoscope 43270
This procedure involves using a flexible tool called an endoscope to identify and remove abnormal growths or polyps in the esophagus, stomach, or upper small bowel. It's a safe way to prevent these growths from causing health issues.
84 services56 patients
Subsequent hospital care with straightforward or low level of medical decision making, per day, if using time, at least 25 minutes 99231
Follow-up hospital inpatient care is a daily service where a healthcare professional checks on your health progress during your hospital stay. Each session typically lasts 15 minutes, involving updates on your condition and adjustments to your treatment plan, if necessary.
56 services29 patients

Hospital Affiliations CMS Care Compare 2

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

Massachusetts General Hospital

Acute Care Hospitals · Boston, MA
5/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number220071
Location55 Fruit StreetBoston, MA 02114 · Suffolk County
Emergency services Birthing friendly

Brigham And Women's Hospital

Acute Care Hospitals · Boston, MA
5/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number220110
Location75 Francis StreetBoston, MA 02115 · Suffolk County
Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 02114 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$144.11 typical visit price
range $63.72 – $189.86
Typical copayment $36.02 (range $15.93 – $47.46)
Most-billed visit code 99204
Established Patient
$111.18 typical visit price
range $21.07 – $155.29
Typical copayment $27.79 (range $5.26 – $38.82)
Most-billed visit code 99214
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

Pathology (Anatomic Pathology)
55 FRUIT ST
BOSTON, MA 02114
Internal Medicine (Hematology & Oncology)
55 FRUIT ST
BOSTON, MA 02114
Anesthesiology
55 FRUIT ST, GRAY-BIGELOW 444
BOSTON, MA 02114
Physical Medicine & Rehabilitation
55 FRUIT ST
BOSTON, MA 02114
Internal Medicine (Infectious Disease)
55 FRUIT ST, DIVISION OF INFECTIOUS DISEASE, GRJ-504
BOSTON, MA 02114
Nurse Practitioner (Acute Care)
55 FRUIT ST, BIGALOW 852 F
BOSTON, MA 02114
Nurse Practitioner
55 FRUIT ST
BOSTON, MA 02114
Internal Medicine (Cardiovascular Disease)
55 FRUIT ST
BOSTON, MA 02114

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Norman Nishioka's NPI number?

The NPI number for Norman Nishioka is 1174513600. It was assigned to this individual provider in the NPPES registry on October 26, 2005.

Where is Norman Nishioka located?

Norman Nishioka practices at 55 Fruit St Gastroenterology Associates Blk 4, Boston, MA 02114. The listed phone number is (617) 726-4422.

What is Norman Nishioka's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Gastroenterology, with taxonomy code 207RG0100X.

Is Norman Nishioka enrolled in Medicare?

Yes. Norman Nishioka is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

What insurance does Norman Nishioka accept?

Health plans from Anthem Blue Cross and Blue Shield list Norman Nishioka as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

Is Norman Nishioka affiliated with any hospitals?

According to CMS data, Norman Nishioka is affiliated with Massachusetts General Hospital and Brigham And Women's Hospital.

When was this NPI record last updated?

The NPPES record for Norman Nishioka was last updated on July 13, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 36 days ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.