Mold Allergies: Causes, Symptoms and Relief

More mold. More allergies.

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Mold is a diverse and widespread group of fungi that lives just about anywhere. Certain types can cause allergic reactions.

Throughout this page, you will find information about:

What is mold?
Causes of mold allergy symptoms?
Where does mold grow?
How can I avoid mold?

Fungus among us all year long

Mold and mildew are tiny fungi. They can live anywhere at any time of the year. So, if you have allergic symptoms that occur through several seasons, you might be allergic to mold.

There are hundreds of types of molds, but not all of them cause allergy symptoms. The most common allergy-causing molds include Alternaria, Aspergillus, Cladosporium, and Penicillium.

Where does mold grow?

Mold thrives in a multitude of environments, both indoors and outdoors. Some thrive in dry, windy weather, while others prefer damp, humid dwellings. Four primary things contribute to mold growth:





Mold allergy causes and symptoms

Once mold finds a place where it would like to live, it starts spreading through spores or seeds. 

When the spores are disturbed, either by touch or air currents, they can spread rapidly. They flow around in the air and cause allergic reactions. When you come into contact with mold spores, your immune system treats it as an allergen and releases antibodies called Immunoglobulin E (IgE). These antibodies travel to cells that release chemicals, causing an allergic reaction.

Typical allergy symptoms like sneezing, watery eyes, and runny nose are all ways your body rids itself of allergens.

Tips to minimize mold exposure

I wish we had better news for you, but unfortunately, it’s impossible to to avoid all allergens. However, there are a few things you can do to help reduce mold exposure:

  • When you’re inside:
    • Keep doors and windows shut
    • Use dehumidifiers
    • Run an air conditioner or air filter with a with HEPA certified filter
    • Keep your home as clean as possible to minimize mold and mildew — especially in dark or damp areas like basements, bathrooms, and around sinks — and clean using a protective mask when needed
    • If mold persists, seek the help of a professional service to remove it
  • When you’re outside:
    • Avoid outdoor activities early in the morning or late in the evening, when mold spore counts are highest
    • Wear a dust mask when cutting grass, digging around plants, picking up leaves, and disturbing other plants
    • Shower after being outdoors
  • Do not disturb mold unless you’re properly educated on mold removal — Read and follow directions for any mold and mildew cleaning products
  • Start taking medications as soon as you notice allergy symptoms
  • Speak to your doctor for more information on allergies
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    1. Asthma and Allergy Foundation of America, Editors. Mold Allergy, Asthma and Allergy Foundation of America (, 2021

    2. American Academy of Allergy, Asthma, and Immunology, Editors. Mold Allergy, American Academy of Allergy, Asthma, and Immunology (, 2021

    3. Andrew Moore, MD, FAAAAI, Reviewer. Outdoor Allergens, American Academy of Allergy, Asthma & Immunology (, September 28, 2020

    4. Jonathan Corren, MD. Allergic rhinitis: Treating the adult, The Journal of Allergy and Clinical Immunology, June 1, 2000

    5. Asthma and Allergy Foundation of America, Ed. Control Allergens to Improve Indoor Air Quality, Reviewed by Medical Scientific Council, 2015.

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