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Internal Medicine

Shunpei Iwata, MD

Sees patients in Pasadena, CA · California

Summary

Dr. Shunpei Iwata, MD is an internal medicine doctor at 800 Fairmount Ave, Suite 410, Pasadena, CA 91105. Phone: (626) 535-0900. Accepts Medicare assignment. In 2024, Shunpei Iwata had 247 Original Medicare patients and 1,322 services. NPI 1396931309. Source: CMS National Downloadable File, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: Internal medicine doctor (Medicare lists Internal Medicine)
  • Address: 800 Fairmount Ave, Suite 410, Pasadena, CA 91105 · Directions
  • Phone: (626) 535‑0900
  • Medicare: Accepts Medicare assignment
  • Medical school: University Of Vermont College Of Medicine · graduated 2004 (22 years since medical school)
  • Gender (as listed): Male

From official Medicare data

This page shows what Medicare's official clinician data says about Shunpei Iwata, joined by NPI number (data updated October 2, 2026). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

Quick answers

Does Shunpei Iwata accept Medicare assignment?
Yes. Medicare's clinician data says Shunpei Iwata accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
How many Medicare patients does Shunpei Iwata see?
In 2024, CMS data shows 247 Original Medicare patients and 1,322 services for Shunpei Iwata. This counts Original Medicare only and measures volume, not quality.
What is Shunpei Iwata's NPI number?
1396931309. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Medicare activity in 2024

Official CMS public-use data for Shunpei Iwata, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.

Original Medicare patients247
Services billed to Medicare1,322
Different services or procedures12
Participating Medicare providerYes
Average age of these patients76

Most frequent services

  1. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)663 services
  2. Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)190 services
  3. Annual wellness visit, includes a personalized prevention plan of service (pps), subsequent visit (G0439)185 services
  4. Annual depression screening, 5 to 15 minutes (G0444)169 services
  5. Influenza vaccine, trivalent, 0.5 ml dosage (90658)26 services

Chronic conditions among these patients

Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).

  • High blood pressure75%
  • High cholesterol75%
  • Diabetes75%
  • Arthritis30%
  • Ischemic heart disease13%
  • Osteoporosis13%

Practice locations

Addresses where Shunpei Iwata is enrolled with Medicare (CMS data updated October 2, 2026).

Specialties

Find other Internal Medicine doctors in California →

Other internal medicine doctors in Pasadena

Clinicians with the same Medicare primary specialty in Pasadena, CA — not a recommendation.

All internal medicine doctors in Pasadena →

Clinician information

CredentialMD
Medical schoolUniversity Of Vermont College Of Medicine
Graduation year2004 (22 years since medical school)
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1396931309
CorrectionsReport an error or suggest an update →

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

  1. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  2. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  3. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  4. Medicare Care Compare — official Medicare tool to look up clinicians