Dr. Thomas Diamant, MD | Costa Mesa, CA | Pulmonology

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Dr. Thomas Diamant is a pulmonologist with 47 years of experience treating patients with lung and breathing conditions. He earned his medical degree from McGill University Faculty of Medicine and completed his residency at Toronto General Hospital. Dr. Diamant speaks English and brings nearly five decades of expertise to his pulmonary medicine practice.

Dr. Diamant is affiliated with Hoag Hospital Newport Beach and practices in Costa Mesa, California. He specializes in treating asthma in both adult and pediatric patients, as well as rhinitis. His practice includes pulmonary function testing to evaluate lung capacity and breathing patterns, along with bronchodilator reversibility testing to assess how well medications can improve airflow. He also performs newborn pulse oximetry screening to check oxygen levels in infants.

AI-generated from data on this provider profile.

2.1

9 Ratings
47 years of experience
31 insurance plans accepted
speaks English
Toronto General Hospital
8 written reviews
1 specialty
7 areas of expertise
1 board certification
1 hospital affiliation
2 office locations
Male

Flexible scheduling

Based on patient feedback. Read the reviews

Dr. Diamant's Ratings and Reviews

2.1

9 Ratings with 8 written Reviews

Average Wait Time 20 Minutes

How was your appointment with
Dr. Diamant?

Patients’ Perspective

Gave an accurate diagnosis: (3) Did WellNeeds Improvement (4)
Had a good bedside manner: (3) Did WellNeeds Improvement (3)
Spent time with me: (4) Did WellNeeds Improvement (3)
Provided follow-up after the visit: (3) Did WellNeeds Improvement (3)
Flexible scheduling: (5) Did WellNeeds Improvement (2)
Saw me in a timely manner: No Ratings
Staff was courteous: No Ratings

9 ratings & reviews

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Showing 1 to 8 of 8 reviews

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The staff were warm and caring. Dr. Diamant however lacked compassion and was condenscending, almost sneering. I felt like I was the least important part of his day.

April 17th, 2026

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Dr Diamant showed no compassion and did not care about patients' concern. The staff was equally rude and condescending. I will never come back.

December 3rd, 2022

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How does he even have 2 stars! It has taken me a long time to write this. He had no compassion no interest in helping his patients. In a hurry and rude. He told me I will end up in the hospital w a life threatening asthma attack. Thank goodness I found a decent pulmonologist and don’t ha. To deal with this person

September 14th, 2022

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No bedside manner. Talks over you. Don’t listen when he asks questions! He kept complaining “ why I don’t have all the paperwork, although all the results is in the website! He is rude. Never, ever want to mention his name again.

December 11th, 2021

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Stay away from this Dr. He has anger issues and does not care what you have to say. I've NEVER had such a rude doctor.

April 19th, 2018

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He is a exceptional Dr. He saved my life. I was a long time patient of his and due to my insurance change I could no longer continue with him. I would highly recommend him to anyone that suffers from Pulmonary diseases.

October 20th, 2015

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This dr. Has a temper I would not see him!

July 20th, 2012

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Dr Diamant and his staff were thorough and displayed genuine concern for me during all office visits and testing. I highly recommend them.

April 4th, 2010

Dr. Thomas Diamant

136 BroadwayCosta Mesa, CA 92627

Tel: (949) 873-5537

College Hospital Costa Mesa

301 Victoria StCosta Mesa, CA 92627

Tel: (949) 642-2734


Dr. Thomas Diamant, MD	Dr. George Shahinian, MD	Dr. Asad Javed, MD	Dr. Lakshminarayana N Tadimeti, MD
Pulmonology	Pulmonology	Pulmonology	Critical Care Medicine
		Accepts New Patients	Accepts New Patients
2.1 (9 Ratings)	4.8 (26 Ratings)	5 (2 Ratings)	5 (1 Rating)
47 Years of Experience	30 Years of Experience	16 Years of Experience	44 Years of Experience
No Virtual Visit Option	No Virtual Visit Option	No Virtual Visit Option	No Virtual Visit Option
Speaks English	Speaks English, Spanish	Speaks English, Hindi, Urdu	Speaks English
Costa Mesa , CA	Laguna Beach , CA	Orange , CA	Manteca , CA
Med School: Mc Gill Univ Fac Of Med	Med School: St Georges University School Of Medicine	Med School: American University Of Antigua College Of Medicine	Med School: Osmania Medical College
Current Profile	View Profile	View Profile	View Profile

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Pulmonology

Angiographic Visualization
Asthma
Chest Infection
Chronic Obstructive Pulmonary Disease (COPD)
Emphysema
Pneumonia
Tuberculosis (TB)

MEDICAL LICENSE

Medical Doctor, California, 2026, Active

EDUCATION & TRAINING

Residency

Toronto General Hospital

Medical School

Mc Gill Univ Fac Of MedGraduated in 1979

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Where is Dr. Thomas Diamant's office located?: Dr. Thomas Diamant's office is located at 136 Broadway, Costa Mesa, CA, 92627.
Does Dr. Thomas Diamant accept virtual/telehealth appointments?: Dr. Thomas Diamant has not indicated that they accept virtual/teleheatlh appointments. Contact their office through their Vitals profile to check for availability.
How can I make an appointment with Dr. Thomas Diamant?: You can find contact information for Dr. Thomas Diamant here on Vitals.
Does Dr. Thomas Diamant accept my insurance?: You can see the insurance plans that Dr. Thomas Diamant accepts on their Vitals profile.
Which hospitals is Dr. Thomas Diamant affiliated with?: Dr. Thomas Diamant is affiliated with Hoag Hospital Newport Beach.

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