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Internal Medicine

Carl W. Buckhorn, MD

Works at hospitals in Fullerton, CA · California

Summary

Dr. Carl W. Buckhorn, MD is an internal medicine doctor at 2282 N State College Blvd, Fullerton, CA 92831. Phone: (657) 378-9888. Accepts Medicare assignment. In 2024, Carl W. Buckhorn had 75 Original Medicare patients and 252 services. NPI 1649264847. 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: 2282 N State College Blvd, Fullerton, CA 92831 · Directions
  • Phone: (657) 378‑9888
  • Medicare: Accepts Medicare assignment
  • Hospital: Providence St. Jude Medical Center
  • Medical school: graduated 1990 (36 years since medical school)
  • Gender (as listed): Male
  • Telehealth: offered

From official Medicare data

This page shows what Medicare's official clinician data says about Carl W. Buckhorn, 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 Carl W. Buckhorn accept Medicare assignment?
Yes. Medicare's clinician data says Carl W. Buckhorn 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 Carl W. Buckhorn see?
In 2024, CMS data shows 75 Original Medicare patients and 252 services for Carl W. Buckhorn. This counts Original Medicare only and measures volume, not quality.
What is Carl W. Buckhorn's NPI number?
1649264847. 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 Carl W. Buckhorn, 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 patients75
Services billed to Medicare252
Different services or procedures16
Participating Medicare providerYes
Average age of these patients72

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)123 services
  2. Telephone medical discussion with physician, 11-20 minutes (99442)50 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 pressure67%
  • High cholesterol45%
  • Arthritis37%
  • Anxiety33%
  • Diabetes31%
  • Depression28%

Hospitals where Carl W. Buckhorn works

Medicare's Facility Affiliation Data lists Carl W. Buckhorn 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 Carl W. Buckhorn is enrolled with Medicare (CMS data updated October 2, 2026).

Specialties

Find other Internal Medicine doctors in California →

Other internal medicine doctors in Fullerton

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

All internal medicine doctors in Fullerton →

Clinician information

CredentialMD
Graduation year1990 (36 years since medical school)
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
TelehealthOffers telehealth services
NPI (National Provider Identifier)1649264847
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