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Hal S Shimazu, MD

Hal S Shimazu, MD

Optum Provider

Specialty

Family Medicine

Languages

English

Seeing patients at

Patient Reviews

Patient review summary

Learn about our survey

5

4

3

2

1

5.0

24 reviews

    • Reviewed on Jul 30, 2026
    • Verified Review

    Dr. Shimazu has always impressed me with his encyclopedic knowledge. In the beginning, we spoke so fast and shared so much, I had difficulty keeping up, but we have since worked out a rhythm together. I always feel like I'm in good hands with Dr. Shimazu.

    • Reviewed on Jul 24, 2026
    • Verified Review

    Dr Shimazu cares about his patients.

    • Reviewed on Jul 24, 2026
    • Verified Review

    He’s knowledgable, helpful, and compassionate.

    • Reviewed on Jul 22, 2026
    • Verified Review

    Dr. Shimazu is an extremely caring doctor who cares for the well being of his patients. He spends time listening and answering your questions. Dr. Shimazu is a very dedicated doctor.

    • Reviewed on Jul 10, 2026
    • Verified Review

    Very caring and takes the time listening to concerns with each visit

    • Reviewed on Jul 8, 2026
    • Verified Review

    professional, thorough, kind

    • Reviewed on Jun 17, 2026
    • Verified Review

    Dr. Shimazu is great! He's knowledgeable, personable, and down-to-earth.

    • Reviewed on Jun 16, 2026
    • Verified Review

    He is to the point, provides answers to all questions and has been a great friend over all these years i have gone to him. Best Dr I have ever had.

    • Reviewed on Jun 15, 2026
    • Verified Review

    great doctor!! very thorough and caring

    • Reviewed on Jun 14, 2026
    • Verified Review

    Dr. Shimazu is so thorough with each of my appointments!! I have never felt rushed with him! He is very knowledgeable and takes time to explain things to me!! I appreciate his care for me!!

    • Reviewed on Jun 12, 2026
    • Verified Review

    He is always very thorough with everything and listens to what we have to say.

    • Reviewed on Jun 12, 2026
    • Verified Review

    I have known Dr. Shimazu to be an excellent doctor ever since I became his patient several years ago. He is able to correctly diagnosis my condition even before obtaining proof by sending me for blood tests, etc. He promptly refers me to proper specialists when necessary. I certainly appreciate having Dr. Shimazu as my treating physician.

    • Reviewed on Jun 11, 2026
    • Verified Review

    I feel Dr. Shimazu is the BEST doctor I have had and has real interest in my health. He does talk fast(who wouldn’t with the computer system you have) but asks me pertinent health questions to better understand my lab results. I’m happy to have found such an excellent doctor!

    • Reviewed on Jun 9, 2026
    • Verified Review

    He's very thorough and caring and knowledgeable. He is also funny and easy to get along with which makes the experience so much better.

    • Reviewed on Jun 5, 2026
    • Verified Review

    Dr Hal Shimazu is an outstanding diagnostician in addition to being thorough, responsive, compassionate, and proactive in coordinating treatment and preventive care, helping me feel confident that my health concerns are being addressed with both expertise and respect.

    • Reviewed on May 30, 2026
    • Verified Review

    He's an old school doctor that knows it all and I trust his medical opinions completely

    • Reviewed on May 26, 2026
    • Verified Review

    very detailed

    • Reviewed on May 22, 2026
    • Verified Review

    Dr. Shimazu explains very easy,

    • Reviewed on May 22, 2026
    • Verified Review

    I'm generally satisfied with his care and treatment and he seems concerned with my health.

    • Reviewed on May 14, 2026
    • Verified Review

    He has a good bedside Manner. Makes me feel comfortable, and good about my health decisions and my efforts at being healthy.

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  • About Hal S Shimazu, MD

    Hal Shimazu, MD, is a family medicine doctor. In addition to his patient practice, Dr. Shimazu also serves as a professor in the Department of Family Medicine at UC Irvine College of Medicine. Patients say that Dr. Shimazu is excellent at diagnosing difficult-to-understand diseases and conditions, such as Lyme disease. They add that he is very thor ough and asks a lot of smart questions regarding patients' family medical histories. In his spare time, Dr. Shimazu enjoys working on his computer and spending time with his family and friends. In addition to English, he speaks Spanish.

    Gender

    Male

    Board certifications

    American Board of Family Medicine

    Licenses

    CA, G37057

    Network Name

    OptumCare HealthCarePartners California, Optum Care Network California

    Hospital affiliations

    Providence Saint Joseph Medical Center,St. Joseph Hospital Orange,St/ Joseph Hospital

  • Education

    Medical School

    • University of California, Davis, School of Medicine

      1973

    Residency

    • University of California Irvine, School of Medicine

      Family Medicine

      1977