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John Mersch III, MD
Practice accepting new patients.

John Mersch III, MD

(949) 388-1798
Primary Specialties
  • Pediatrics
Medical Groups & Affiliations
  • Mission Hospital Affiliated Physicians
  • Southern OC Pediatric Assoc.
  • Additional Languages Spoken

Primary Office

777 Corporate Drive, Suite 250
Ladera Ranch, CA 92694
(949) 388-1798
(949) 388-6495
Monday through Friday:
8:00 a.m. - 4:30 p.m.
After hours care available in Ladera Ranch.
Web Page:

Secondary Office

(949) 770-0513
(949) 770-2941

Physician Bio

Dr. Mersch says that even though the bureaucracy of pediatrics has changed remarkably since his beginnings in private practice, it is still fun to go into an exam room and interact with the patient and his/her parents.


Medical School:
University of Southern California

Children’s Hospital, Los Angeles

Children’s Hospital, Los Angeles, Pediatric Chief Resident
  • Board Certified in Pediatrics


American Board of Pediatrics

Areas of Expertise

Sports medicine, asthma, ADD

Areas of Interest


Insurance ID Numbers

Aetna: 298055
Blue Cross: 0XL118
Blue Shield: 00G408870
CIGNA: 3502933014
CIGNA Select (SJH): 3502933016
Health Net: 3207024895
United Healthcare: 183520088

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