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Florence Ida Hsu, MD

Assistant Professor of Medicine (Rheumatology, Allergy & Immunology); Training Program Director - Allergy & Immunology Fellowship, Internal Medicine

Contact Information

Florence Ida Hsu, MD

Patient Care Locations

Mailing Address

  • Allergy & Immunology

    333 Cedar Street, PO Box 208013

    New Haven, CT 06520-8013

    United States


F. Ida Hsu, MD, is an allergist and immunologist who treats a wide range of conditions and illnesses, including asthma, allergic rhinitis, drug hypersensitivity and hives with unknown cause. “I often approach cases as a detective would, looking for clues to an answer—sometimes obvious, and sometimes elusive,” she says. “Having suffered from hives and various allergies when I was younger, I can relate to my patients and provide practical advice.”

An assistant professor of clinical medicine at Yale School of Medicine, Dr. Hsu studied medicine at Columbia University's College of Physicians & Surgeons, trained in Internal Medicine at New York Presbyterian Hospital-Weill Cornell Medical Center, and completed her Allergy and Immunology fellowship at the Brigham & Women's Hospital in Boston, MA, where she served on the clinical faculty for several years before coming to Yale.

Over the years, she has been involved in clinical trials focused on finding new treatments for hereditary angioedema, a rare genetic disorder that causes swelling in the face, upper air passageways and other parts of the body. She also provides specialized care for patients with chronic rhinosinusitis, nasal polyposis, and aspirin-exacerbated respiratory disease, in collaboration with Yale and other community otolaryngologists and pulmonary physicians.

When meeting a new patient, Dr. Hsu says, “First step first: let’s do some testing, figure out what we’re dealing with, and then we can come up with a plan to address your symptoms and get you feeling better.” Sometimes testing is not required, and she is able to make recommendations for medications or non-pharmacologic treatments to help her patients with their allergy or immunology issues.

Education & Training

  • Fellow
    Brigham & Women's Hospital, Boston, MA (2006)
  • Resident
    NewYork-Presbyterian/Weill Cornell Medical Center, New York, NY (2003)
  • Intern
    NewYork-Presbyterian/Weill Cornell Medical Center, New York, NY (2001)
  • MD
    Columbia University Coll of Physicians & Surgeons (2000)
  • BA
    Harvard University, Biology (1994)


  • “Approach to Aspirin/NSAID Drug Allergy”
    Greenwich, CT, United States 2022
    Medical Grand Rounds
  • “Advances in the Clinical Management of Hereditary Angioedema”
    Denver, CO, United States 2021
    Denver Allergy Rounds
  • “Recognition and Management of Aspirin Exacerbated Respiratory Disease (AERD)”
    (Virtual) 2021
    Annual Educational Meeting Connecticut ENT Society (Virtual)
  • “Update in Anaphylaxis”
    New London, CT, United States 2021
    Clinical Science Lecture Series
  • “Allergy Pearls for Primary Care: What Allergists Want You to Know”
    Waterbury, CT, United States 2021
    Medical Grand Rounds
  • “Lower IgG trough and CD4 count may lead to hospitalization for COVID-19 infection in patients on IgG maintenance therapy”
    (Virtual) 2021
    CIS 2020 National Meeting (virtual)
  • “Severe Refractory chronic urticaria and angioedema treated with rituximab”
    (Philadelphia, PA, canceled) 2020
    2020: AAAAI Annual Meeting
  • "Experience with plasma-derived C1-inhibitor in pregnant women with hereditary angioedema: a systematic review of the literature”
    Lisbon, Lisbon, Portugal 2019
    EAACI Congress 2019
  • “HAE in children and pregnant/lactating women”
    Atlanta, GA, United States 2019
    2019 HAEA National Patient Summit, HAE Professional-Scientific Program, Panelist
  • “Clinical Profile and Treatment Outcomes in Patients With Hereditary Angioedema With Normal C1 Esterase Inhibitor”
    Houston, TX, United States 2019
    ACAAI National Meeting
  • “Recombinant Human C1 Esterase Inhibitor as Short-Term Prophylaxis for Dental Procedures in Patients With Angioedema: A Case Series”
    San Francisco, CA, United States 2019
    AAAAI Annual Meeting
  • “Aspirin and Non-steroidal Anti- Inflammatory Drug Allergy”
    Norwalk, CT, United States 2018
    Medical Grand Rounds
  • “Aspirin and Non-steroidal Anti- Inflammatory Drug Allergy”
    Waterbury, CT, United States 2018
    Medical Grand Rounds
  • “Recombinant C1 Esterase Inhibitor for Short-Term Prophylaxis in Patients With Hereditary Angioedema”
    Seattle, WA, United States 2018
    ACAAI Annual Meeting
  • "Functional natural killer cell deficiency presenting as recurrent viral infections”
    Westford, MA, United States 2017
    New England Society of Allergy Spring Meeting
  • “High Dose C1 Esterase Inhibitor Used for Hereditary Angioedema Prophylaxis During Pregnancy”
    Westford, MA, United States 2017
    New England Society of Allergy Spring Meeting
  • A Case of Severe Chronic Idiopathic Urticaria and Angioedema in the Setting of an Elevated Anti-IgE IgG Level”
    Atlanta, GA, United States 2017
    AAAAI Annual Meeting
  • “Hemolysis Associated with IVIG Therapy"
    Los Angeles, CA, United States 2016
    AAAAI Annual Meeting
  • “Expansion Of Circulating T Follicular Helper Cells In CVID Patients With Autoimmune Cytopenias”
    San Diego, CA, United States 2014
    AAAAI Annual Meeting
  • “Difficult Cases (Part 2): Urticaria and Angioedema”
    New Orleans, LA, United States 2010
    American Academy of Allergy Asthma & Immunology Annual Meeting
  • “Allergy Skin and Serum Testing”
    Cambridge, MA, United States 2009
    Pediatric Asthma & Allergy Update for Primary Care Providers, Harvard Medical School
  • “Treating Refractory Chronic Idiopathic Urticaria (CIU)” and “Update in Therapies for Hereditary Angioedema”
    Boston, MA, United States 2009
    Brigham and Women’s Clinical Allergy Conference
  • Dinner Symposium Speaker “Treatment of Hereditary Angioedema: Choice of Modalities: State-of-the-Art: Bradykinin Receptor 2 Inhibitors”
    Washington, DC, United States 2009
    American Academy of Allergy Asthma & Immunology Annual Meeting
  • “Allergy Skin Testing: Theory and Demonstration”
    Boston, MA, United States 2006
    Understanding Allergy, Partners Asthma Center Asthma Educators Institute

Honors & Recognition

AwardAwarding OrganizationDate
Elected to Fellowship (FAAAAI)American Academy of Allergy, Asthma, and Immunology2010
Keystone Symposia ScholarshipEicosanoids in Inflammation and Chronic Diseases Meeting2006
AAAAI/Sepracor Research Excellence AwardAmerican Academy of Allergy Asthma & Immunology2006
AAAAI Third-Year Allergy and Immunology FIT Research AwardAmerican Academy of Allergy Asthma & Immunology2005
Janet M. Glasgow Memorial CertificateAmerican Medical Women’s Association2000
Alpha Omega AlphaCollege Of Physicians & Surgeons1999
Ruth Liu Memorial ScholarshipChinese American Medical Society1999
Dr. Alfred Steiner Research AwardCollege Of Physicians & Surgeons, Columbia University1999
McGraw-Hill Book AwardCollege Of Physicians & Surgeons, Columbia University1997
Phi Beta KappaHarvard College1994
Research Fellowship AwardFord Program for Undergraduate Research, Harvard College1993

Professional Service

Data Safety Monitoring Committee for Protocol ITL-2002-CL-001 entitled “Phase 1/2 Study to Evaluate Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of NTLA-2002 in Adults with Hereditary Angioedema (HAE), Intellia PharmaceuticalsCommittee Member2023 - Present
HAE Advisory Committee, Takeda Pharmaceutical CompanyCommittee Member2021
Virtual Medical Advisory Board, Biocryst PharmaceuticalsBoard Member2021 - Present
COVID-19 Vaccine Medical Exemption Review CommitteeCommittee Member2021 - 2022
COVID-19 Vaccine Clinical Advisory Group, Yale-New Haven Hospital SystemMember2021 - 2022
eConsult Specialist Advisory GroupMember2021 - Present
HAE Virtual Advisory Board,, Takeda Pharmaceutical CompanyBoard Member2020 - Present
Systemic Mastocytosis Advisory Board, Blueprint MedicinesBoard Member2020 - Present
COVID-19 Vaccine Adverse Event Monitoring and VAERS Reporting WorkgroupMember2020 - 2021
Faculty Search Committee, Section of Rheumatology, Allergy & Immunology, Department of Medicine, Yale School of MedicineMember2020 - 2021
Westport Coronavirus Info Facebook group (2300 members) Moderator2020 - 2021
Advances in Hereditary Angioedema (HAE) Prophylaxis Advisory Board, Biocryst PharmaceuticalsBoard Member2019 - Present
Long Lots Elementary School PTACo-Chair2019 - 2021
Chinese Language School of Fairfield County(Registration Chair 2019-2020, 2021-present)2019 - Present
Lanadelumab Virtual Advisory Board, Shire PharmaceuticalsBoard Member2018 - Present
US PRECISION East Advisory Board, Astra-ZenecaBoard Member2018
American Academy of Allergy, Asthma, and Immunology (AAAAI) Division Directors Committee2018 - 2020
Long Lots Elementary School PTACommittee Member2018 - 2019
Faculty Search Committee, Section of Rheumatology, Allergy & Immunology, Department of Medicine, Yale School of MedicineCo-Chair2018
Program Evaluation Committee Allergy and Immunology FellowshipChair2018 - Present
American Academy of Allergy, Asthma, and Immunology (AAAAI)Training Program Director Assembly2018 - Present
HAE Scientific Advisory Board, CSL BehringBoard Member2017 - Present
Chinese Language School of Fairfield CountyBoard of Directors2017
Yale School of MedicineCommittee Member2016 - Present
JACI: In PracticeReviewer2016 - Present
PediatricsAd-hoc mentored reviewer2013 - 2014
CT-Moms OnlineCoordinator2012 - 2014
American Academy of Allergy, Asthma, and Immunology (AAAAI)FADDA Abstract Review Committee2010 - 2011
American Academy of Allergy, Asthma, and Immunology (AAAAI)Elected to Fellowship in March 20102010 - Present
The Journal of Allergy and Clinical ImmunologyReviewer2010 - Present
American Academy of Allergy, Asthma, and Immunology (AAAAI)NAIA Annual Meeting Programming Committee2009 - 2010
New Allergist/Immunologist Assembly (NAIA) Career Pathways Task ForceCo-Chair2009
Allergic Skin Diseases CommitteeMember2008 - 2013
Adverse Reactions to Drugs, Biologicals, and Latex CommitteeMember2008 - 2013
Quincy House, Harvard UniversityAdvisor2008 - 2010
New Allergist/Immunologist Assembly (NAIA) Academic Practice Task ForceVice Chair2008 - 2009
Medical Reserve Corps, Department of Public HealthVolunteer2006 - 2010
Cells and Mediators of Allergic Inflammation CommitteeMember2006 - 2008
Leadership Council, Department of Medicine Society of FellowsMember2005 - 2006
Radcliffe Mentor Program, Harvard UniversityMentor2004 - 2008
Fellows-in-Training CommitteeMember2004 - 2006

Departments & Organizations