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Recent News

Irvine school nurses, staff learn Stop the Bleed techniques to respond in mass-casualty situation

Irvine school nurses and athletic trainers on Tuesday, Jan. 30, learned simple techniques that could save lives in a shooting or other ...

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Families anticipate exciting community blessing of surgical center

A community is as strong as its hospital, and with recent investments into Covenant Health Plainview, it’s evident that to our friends ...

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Severe Flu Season Tightens Its Grip on U.S.

Americans are being hit with one of the worst flu seasons in years, with misery now widespread across 46 states, health officials say. In ...

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About St. Joseph Health

SJH provides a full range of care facilities including 16 acute care hospitals, home health agencies, hospice care, outpatient services, skilled nursing facilities, community clinics and physician groups. All of our hospital and home health entities are accredited by the Joint Commission. In our award-winning facilities, SJH maintains a "continuum of care," matched to the diverse needs of the urban centers, smaller cities and rural communities who depend on us every day.

Marion L. Guyer, MD

4.8 out of 5 (90 Ratings)
  • Internal Medicine
    (Board Certified)
Additional Language Spoken
Medical Groups & Affiliations
  • St. Joseph Health Medical Group
  • St. Joseph Health Medical Network
St. Joseph Health Petaluma - Family Medicine
905 East Washington Street
Petaluma, CA 94952
Accepting New Patients

Primary Office

St. Joseph Health Petaluma - Family Medicine
905 East Washington Street
Petaluma, CA 94952
Get Directions
(707) 763-9891
(707) 762-2311

More Information

  • Meet The Doctor

    Specialties & Education

    Primary Specialties
    • Internal Medicine
      (Board Certified)
    Education & Training
    • College
      Presidio Graduate School - 2010
    • Medical School
      University of California, San Francisco - 1997
    • College
      University of California, Berkeley - 1990
    • College
      Yale University - 1984
    • Internship
      Alameda County Medical Center - 1998
    • Residency
      Alameda County Medical Center - 2000
  • Biography



    Chief of Hospitalist Medicine
    Assistant Medical Director for Care Transitions
    Attending Physician, Inpatient Medicine

  • 3-Mar-2020
    Great experience, excellent care!
    Dr. Guyer listens very closely to me and is very knowledgeable regarding any of my questions.
    very knowledgeable and informative.
    This was my first visit with Dr. Guyer to establish a care relationship and I was very pleased with her knowledge and caring manner.
    very informative/listens attentively/very caring
    44 Total Comments Page 1 2 3 4 5 6 7 8 9   Next