Thomas J. Diamant, MD

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Thomas J. Diamant, MD



  • Hoag Physician Partners


  • English

About Dr. Diamant

Raised in Montreal, Dr. Diamant studied at McGill University in the Accelerated Pre-Medical Program, during which time he was recognized each year by the Faculty of Medicine as a McGill University Scholar.

He began his Internship training in Straight Medicine at Toronto General Hospital and continued his training as a Resident in Internal Medicine at St. Mary Medical Center, Long Beach. In 1984, Dr. Diamant completed his Fellowship in Respiratory Physiology and Medicine at Harbor-UCLA Medical Center in Torrance. He received Board Certification in Internal Medicine in 1984, in Pulmonary Medicine in 1988, and in Critical Care Medicine in 1991.

Apart from his clinical research, Dr. Diamant served as Medical Director in the Pulmonary Rehabilitation Program and as Medical Director in the Sleep Abnormalities Laboratory at St. Mary Medical Center, Long Beach. He has served as Chairman of the Division of Pulmonary Medicine at Hoag Hospital as well as Chairman of the Department of Internal Medicine. Dr. Diamant holds an appointment as the Medical Director of the Hoag Hospital Department of Respiratory Care and is a Fellow of the College of Chest Physicians.

Dr. Diamant enjoys cycling in his spare moments and spending time with his family.


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National Provider ID (NPI): 1952310872


  • Medical Education - McGill University (Medical Doctor)
  • Internship - Toronto General Hospital (Rotating)
  • Residency - Saint Mary Medical Center-Long Beach (Internal Medicine)
  • Fellowship - Harbor-UCLA Medical Center (Pulmonary)

Board Certification

  • American Board of Internal Medicine - Internal Medicine
  • American Board of Internal Medicine - Pulmonary Disease


  • Hoag Physician Partners

Area of Focus

  • Pulmonary