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Internal Medicine

Amer H. Muhyieddeen, MD

Works at hospitals in Fontana, CA · California

Summary

Dr. Amer H. Muhyieddeen, MD is an internal medicine doctor at 9961 Sierra Ave, Fontana, CA 92335. Phone: (909) 427-5000. Accepts Medicare assignment. In 2024, Amer H. Muhyieddeen had 11 Original Medicare patients and 33 services. NPI 1508328527. Source: CMS National Downloadable File, updated October 2, 2026; CMS Facility Affiliation Data, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: Internal medicine doctor (Medicare lists Internal Medicine)
  • Address: 9961 Sierra Ave, Fontana, CA 92335 · Directions
  • Phone: (909) 427‑5000
  • Medicare: Accepts Medicare assignment
  • Hospital: Kaiser Foundation Hospital Fontana/Ontario
  • Group practice: Southern California Permanente Medical Group
  • Medical school: graduated 2019 (7 years since medical school)
  • Gender (as listed): Male

From official Medicare data

This page shows what Medicare's official clinician data says about Amer H. Muhyieddeen, 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 Amer H. Muhyieddeen accept Medicare assignment?
Yes. Medicare's clinician data says Amer H. Muhyieddeen 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 Amer H. Muhyieddeen see?
In 2024, CMS data shows 11 Original Medicare patients and 33 services for Amer H. Muhyieddeen. This counts Original Medicare only and measures volume, not quality.
What is Amer H. Muhyieddeen's NPI number?
1508328527. 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 Amer H. Muhyieddeen, 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 patients11
Services billed to Medicare33
Different services or procedures3
Participating Medicare providerYes
Average age of these patients80

Most frequent services

  1. Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes (99232)25 services

Hospitals where Amer H. Muhyieddeen works

Medicare's Facility Affiliation Data lists Amer H. Muhyieddeen at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.

Practice locations

Addresses where Amer H. Muhyieddeen is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Amer H. Muhyieddeen as a member of this group (CMS data updated October 2, 2026).

  • Southern California Permanente Medical Group11,293 clinicians in the group

Specialties

Find other Internal Medicine doctors in California →

Other internal medicine doctors in Fontana

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

All internal medicine doctors in Fontana →

Other clinicians in Southern California Permanente Medical Group

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

Clinician information

CredentialMD
Graduation year2019 (7 years since medical school)
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1508328527
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. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
  2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
  3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  6. Medicare Care Compare — official Medicare tool to look up clinicians