Dr. Jonathon Ahn, MD

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Payments from drug and device companies, 2025

Drug and device makers are required by federal law (the Physician Payments Sunshine Act) to report what they pay or give to clinicians, and CMS publishes the reports as Open Payments. This is the 2025 program year. A report is a record of a payment, not an allegation of anything, and many are small items such as meals. Only general payments are listed here; research payments and ownership or investment interests are reported separately by CMS and are not shown.

Each amount is the sum of what companies reported for that kind of payment in 2025, rounded to the dollar. Not all of it is income to the clinician: a meal is not a fee, a charitable contribution goes to a charity, and a royalty or an acquisition payment is not a salary.

Check a report, or dispute one, at the source in CMS’s own tool, Open Payments. Corrections go through CMS’s dispute process. This site removes a home address on request and asks for no proof, because that is privacy; it will not remove an accurate payment report on request, because that is a statutory public disclosure.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician.

• Providence St. Jude Medical Center Hospital · Fullerton, CA

Colleagues at Allied Anesthesia Medical Group Inc

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 184 clinicians in the practice; 12 are shown here.

• Christine C Chow, MD Anesthesiology Physician · Upland, CA
• Mr. Monte Morris Christen, CRNA Certified Registered Nurse Anesthetist · Los Angeles, CA
• Jonathan D. Cohen, MD Anesthesiology Physician · Orange, CA
• Dr. Dale L Davis, MD Anesthesiology Physician · Upland, CA
• Dr. Edward Sunro Lee, MD Anesthesiology Physician · Torrance, CA
• Pedro Lopez, MD Anesthesiology Physician · Upland, CA
• Vincent Luo, MD, PHD, MPHIL Anesthesiology Physician · West Hollywood, CA
• Dr. Rebekah Nam, MD Student in an Organized Health Care Education/Training Program · New York, NY
• Mark R Poblete, MD Surgery Physician · Encino, CA
• Dr. Ahmed A. Serag, MD, PHD Anesthesiology Physician · Irvine, CA
• Dr. Larry Vazquez, MD Anesthesiology Physician · Chicago, IL
• Marc L. Weller, MD Anesthesiology Physician · Pomona, CA

Other providers in Fullerton

• David Evan Bergman, DO

  Individual Anesthesiology Physician · NPI 1801848866

  101 E Valencia Mesa Dr, Fullerton, CA 92835-3809 · (714) 871-3280

• Richard Charles Bollin Jr., MD

  Individual Anesthesiology Physician · NPI 1306898366

  101 E Valencia Mesa Dr, Fullerton, CA 92835-3809 · (714) 871-3280

• California Anesthesia Group PC

  Organization Anesthesiology Physician · NPI 1477114742

  295 Imperial Hwy Ste 200B, Fullerton, CA 92835-1020 · (714) 770-8366

• Joseph Emil Cochoit, MD

  Individual Anesthesiology Physician · NPI 1679525612

  101 E Valencia Mesa Dr, Fullerton, CA 92835-3809 · (714) 871-3280