Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.
NPIDirectory

Dr. Marilyn Mae McGowan, MD

Individual provider Internal Medicine Physician · NPI 1417586835

Dr. Marilyn Mae McGowan, MD practises Internal Medicine in San Luis Obispo, California. Graduated from Georgetown University School of Medicine in 2020, 6 years ago. Practices with David B. Hammer, a 116-clinician group, accepts Medicare assignment and offers telehealth. Licensed in California.

Years since qualifying
6
Trained at
Georgetown University School of Medicine
Licensed in
CA
In the registry since
2020
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

See every abbreviation used in this directory →

Claim this listing Report a problem Suggest an edit

Practice location Address checks out

892 Aerovista Pl Ste 210
San Luis Obispo, CA 93401-8054
Phone: (805) 549-8023
Show map & directions

Directions in Google Maps · Apple Maps · OpenStreetMap

Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Internal Medicine Physician (primary) Taxonomy 207R00000X · Licence A193400 (CA)

Record details

NPI number1417586835
Entity typeIndividual (Type 1)
GenderFemale
Credentials MD
Sole proprietorNo
NPI enumeratedApril 7, 2020
Last updated in NPPESAugust 27, 2024
Certification dateAugust 27, 2024

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyINTERNAL MEDICINE
Medical schoolGEORGETOWN UNIVERSITY SCHOOL OF MEDICINE
Graduated 2020 (6 years in practice)
Group practice David B. Hammer — 116 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services
Practice locations4 on file with Medicare

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.

Medicare patients440
Services billed 864 a service is one billed item, such as a visit, a test or a procedure
Average patient age74

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.

Food and Beverage $84 4 payments · a meal or drink at a meeting or visit, not a fee

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. Those with a page here are linked.

  • Ronald Reagan Ucla Medical Center Hospital · Los Angeles, CA
  • Aevum Home Health Home health agency · San Luis Obispo, CA · listed as Aevum Home Health Inc
  • Central Coast Home Health Inc Home health agency · San Luis Obispo, CA · listed as Central Coast Home Health, Inc
  • Dignity Health Home Health Home health agency · Santa Maria, CA · listed as Dignity Health
  • Adventist Health Sierra Vista Hospital · San Luis Obispo, CA
  • French Hospital Medical Center Hospital · San Luis Obispo, CA
  • Marian Regional Medical Center Hospital · Santa Maria, CA

Colleagues at David B. Hammer

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 116 clinicians in the practice; 12 are shown here.

Other providers in San Luis Obispo