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Dr. Thomas Mercier, MD

Dr. Thomas Mercier, MD

Pediatrics*
45+ years of experience

Dr. Thomas Mercier, MD is a pediatrician in Mattituck, NY and has over 45 years of experience in the medical field. He graduated from PENNSYLVANIA STATE UNIVERSITY / ABINGTON-OGONTZ CAMPUS in 1977. He is affiliated with medical facilities Stony Brook University Hospital and Peconic Bay Medical Center.

4.6 Star Rating
Based on 9 reviews 4.6 Star Rating (9 reviews)

Practice

700 New Suffolk Ave Mattituck, NY 11952

At a Glance

  • Area of Expertise
    Dr. Mercier specializes in the area of Pediatrics. See board certifications
  • Explains Conditions Well
    Patients said this doctor explains conditions well. See reviews
  • Practices at Top Hospital
    America's 100 Best Hospitals Award™ See hospitals
  • Clean Hospital
    Patients said the hospital this doctor practices at is clean. See hospitals
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Dr. Mercier's Reviews

Likelihood to recommend Dr. Mercier

4.6
9 ratings, 1 with written review
5 star
89%
89%
4 star
0%
0%
3 star
0%
0%
2 star
0%
0%
1 star
11%
11%

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Didn’t believe me and didn’t help me
When I turned 18 Dr. Mercier retired. I am now writing this years later because I feel it’s important for anyone else who experienced something similar to know it wasn’t only them. I complained about chest pain & he said I was copying my sibling because I was jealous & wanted attention. My sibling has a hole in their heart & he never thought I could have the same thing happening - just said I was pretending even though I had so much chest pain. I would also go to him every 1-3 months sick, unable to breathe properly; severe cough; bloodshot eyes; nasal infections; etc. I’d be sick for weeks on end & he’d say it was a simple cold or seasonal allergies. Once I hit 18, I went without my parents & demanded a referral to an ENT specialist. I found an amazing doctor who immediately knew I had asthma by just speaking with him. Later did testing to confirm my asthma & I had a severe allergy to mold. I was immediately placed on a treatment plan & I haven’t been sick in years.
What went well
No results
What could be improved
  • I didn't feel respected
  • Didn't listen or answer questions
  • Didn't trust the provider's decisions
1 other person found this helpful
Helpful
Jun 16, 2024
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About Me

biography

Dr. Thomas Mercier, MD is a pediatrician in Mattituck, NY and has over 45 years of experience in the medical field. He graduated from PENNSYLVANIA STATE UNIVERSITY / ABINGTON-OGONTZ CAMPUS in 1977. He is affiliated with medical facilities Stony Brook University Hospital and Peconic Bay Medical Center.
  • Pediatrics

*Healthgrades does not verify qualifications for medical specialties. Please verify your provider's specialty and qualifications directly with your provider and applicable medical board.

  • Pennsylvania State University / Abington-ogontz Campus

    Medical School, 1977
American Board of Medical Specialties®
American Board of Pediatrics®
Pediatrics
For detailed information about any of the below board actions, please search for the provider's records on the linked state licensing board or the Federation of State Medical Boards. To learn more about the difference between these sources, please refer to our FAQs.
Healthgrades has not received any data indicating a board action exists for this provider.
  • English

  • Spanish

Locations

Practice

Office700 New Suffolk Ave Mattituck, NY 11952
1

Affiliated Hospitals

  • Peconic Bay Medical Center

    1 Heroes Way
    Riverhead, NY 11901
    Recipient of 11
    hospital awards

    How patients felt about the care they received at this hospital.

    86%
    Patients said they were given information about recovering at home

    2% higher than the national average

    75%
    Patients said that doctors always listened to them and explained things well

    1% lower than the national average

    View all patient feedback
  • Stony Brook University Hospital

    101 Nicolls Rd
    Stony Brook, NY 11794
    Recipient of 33
    hospital awards

    America's 100 Best Hospitals Award™ (2025, 2024, 2023)

    Top 1% in the nation for providing the highest clinical quality year over year

    America's 250 Best Hospitals Award™ (2025, 2024, 2023)

    Top 1% in the nation for providing the highest clinical quality year over year

    View all awards

    How patients felt about the care they received at this hospital.

    86%
    Patients said they were given information about recovering at home

    2% higher than the national average

    74%
    Patients said that doctors always listened to them and explained things well

    2% lower than the national average

    View all patient feedback
Learn more about how Healthgrades measures Hospital Quality