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Shirin Alonzo, MD

COVID-19 update:

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Dr. Shirin Alonzo, MD


Phone Number
Scripps Coastal San Marcos Internal Medicine
111 Campus Way
San Marcos, CA 92078
Get directions
Accepts new patients


  • Internal Medicine


Shirin Alonzo, MD, provides comprehensive primary care for all ages. She partners with her patients so they can make informed decisions to advance their well-being. Dr. Alonzo believes everyone has the right to the highest quality, compassionate health care in a nurturing and nonjudgmental environment.

In addition to her medical degree, Dr. Alonzo earned her master of public health degree from Harvard University. She has expertise in global health and transitional care for vulnerable populations, including those with intellectual and physical challenges. She also has a special interest in patients needing complex care.

Dr. Alonzo enjoys volunteerism, basketball, surfing, hiking, Thai boxing, oil painting and traveling.

Board Certifications

  • American Board of Pediatrics, Pediatrics, 2014
  • American Board of Internal Medicine, Internal Medicine, 2014

Medical Education

  • University of California, San Diego, MD, 2010


  • University of California, San Diego School of Medicine, Internal Medicine-Pediatrics, 2014


  • University of California, San Diego, Neurodevelopmental Disabilities, 2015
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