Courtney A. O'Brien, DO
Accepting New Patients

Courtney A. O'Brien, DO

  • Rheumatology
Average rating: 5.0
 
Simi Valley Primary & Specialty Care |
2655 1st Street, Suite 380, Simi Valley, CA 93065
805-583-7640
+1 more location
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About

Dr. Courtney O’Brien is a board certified rheumatologist who practices in Simi Valley and Porter Ranch. She provides comprehensive care in general rheumatology with particular clinical interests in musculoskeletal ultrasound, osteoporosis, lupus, vasculitis, and inflammatory arthritis.

Dr. O’Brien earned her medical degree from Nova Southeastern University College of Osteopathic Medicine, where she received additional training in osteopathic manipulative medicine, emphasizing a holistic approach to patient care. Her passion for rheumatology was sparked early in her medical education through volunteer work with children affected by juvenile arthritis. She went on to complete her internal medicine residency at Rush University Medical Center in Chicago and her rheumatology fellowship at UCLA. She is certified in musculoskeletal ultrasound through the USSONAR program and integrates this advanced imaging technique into her clinical evaluations to ensure accurate and thorough diagnostic assessments.

Dr. O’Brien is also dedicated to global health and has participated in numerous medical outreach initiatives throughout Latin America and the Caribbean, delivering care to underserved populations. 

In her leisure time, Dr. O’Brien enjoys a variety of outdoor activities, including hiking, paddle boarding, skiing, roller skating, camping, and beach volleyball.

Languages

English

Education

Medical Board Certifications

Rheumatology, American Board of Internal Medicine, 2022
Internal Medicine, American Board of Internal Medicine, 2020

Fellowship

Rheumatology, University of California, Los Angeles, 2022

Residency

Internal Medicine, Rush University, 2020

Degree

DO, Nova Southeastern University College Of Osteopathic Medicine, 2017

Recognitions

  • Super Doctors® Southern California Rising Stars 2025

Locations

Hospital Affiliations

Ronald Reagan UCLA Medical Center

Medical Services

Rheumatology

Insurance

  • Aetna
  • Anthem Blue Cross
  • Blue Shield of California
  • Centivo
  • Cigna
  • First Health
  • Health Net of California
  • Interplan (part of HealthSmart)
  • Medicare Advantage
  • MultiPlan
  • UFCM Health System
  • Prime Health Services
  • Private Healthcare Systems (PHCS)
  • TRICARE
  • UnitedHealthcare

The list of health care plans above may not be comprehensive and could change. 
Please contact your benefits coordinator or health insurance company directly to verify coverage.

Visit our health insurance information page for more details.

Recognitions

  • Super Doctors® Southern California Rising Stars 2025

Reviews

Overall Rating:
5.0
212 total ratings | 128 reviews
5.0
August 27, 2025
She was very professional and gave time to listen to my health issues. Since it’s my first appointment with her I really admire she was listening patiently and taking notes at the same time.
5.0
August 27, 2025
Very good
5.0
August 27, 2025
Listens
5.0
August 27, 2025
Listened to me - went over medications and worked out a plan of action.
5.0
August 27, 2025
She is very thorough and takes into account all angles of my health. Very responsive to questions and feedback.
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