Some Important Information About the Symptoms of Mold Allergies.

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Mold Is Everywhere (Almost)

It is estimated that about 5 percent of the world’s population is allergic to mold. Unlike some other allergens, mold is present indoors and outdoors, and poses a health threat all year long to those who are allergic to it. While mold grows on stationary objects, its spores, which are the particle components of mold that cause allergy symptoms, are carried through the air. The airborne spores are then inhaled en masse into the upper respiratory system and lungs, where they wreak havoc in allergy sufferers. Indoor areas that are most likely to support mold growth include damp areas, such as bathrooms, laundry rooms, kitchens, basements and indoor patios, for example. Items that are mostly likely to sustain mold growth include refrigerators, air conditioners, humidifiers and dehumidifiers, books, carpets, wallpaper, wooden objects and garbage cans, to name a few.

Outdoor mold typically is found in the soil, on vegetation such as tree trunks and piles of dead, wet leaves, and in just about any other outdoor area that is frequently damp. Generally, molds grow better indoors than they do outdoors, and it is certainly true that their spore concentrations typically are more dense outdoors.

To provide an idea regarding how ubiquitous mold is, to completely avoid mold, a person would need to visit an extremely clean room that is equipped with very sophisticated air filtration equipment. Specialized rooms of this kind are few in number, and include organ transplant surgical rooms and certain computer chip manufacturing rooms.

What Are the Symptoms of Mold Allergies?

As mold is virtually everywhere around us, it is not surprising that those who are allergic to it have difficulty avoiding it and many have frequent mold-induced allergic outbreaks. These symptoms range from very mild to life-threatening. Factors that affect symptom severity include the amount and the species of mold to which a person is exposed, and the length of time of the exposure.

Specifically, allergic individuals typically experience one or more of the following symptoms during a mold allergy outbreak:

  • Asthma and/or rhinitis (moderately inflamed nasal passages)
  • Itchy and watery eyes
  • Itchy nose and throat
  • Frequent sneezing
  • Shortness of breath
  • Various other respiratory problems (wheezing, cough and excess phlegm production)
  • Chest tightness
  • Hypersensitivity pneumonitis (inflammation of the alveoli of the lungs, which are small cavities that are involved in gas exchange with the blood)
  • Allergic bronchopulmonary apergillosis (an airway condition in which airway constriction occurs, thereby making breathing extremely difficult)
  • Allergic fungal sinusitis (a severe and painful inflammation of the paranasal sinuses, which sometimes requires surgery to alleviate)
  • Anaphylaxis (a serious and potentially life-threatening whole body reaction; anaphylaxis is an extremely rare symptom of mold allergy)

If you suspect that you or a loved one may be allergic to mold and you do not have serious symptoms that require immediate attention, it is recommended that you schedule an appointment with an allergist. If you or a loved one has more serious symptoms, you should seek the help of a medical professional right away.


B.D. Hardin et al., Adverse human health effects associated with molds in the indoor environment, Journal of Occupational and Environmental Medicine: 45:47-478 (2003).

B. Simon-Nobbe et al., The Spectrum of Fungal Allergy, International Archives of Allergy and Immunology: 145:58-86 (2007).

Mayo Clinic, Mold Allergy:

Medline Plus, Allergy to mold, animal dander, dust:

National Institute of Environmental Health Sciences, Mold:

R.K. Bush et al., The medical effects of mold exposure, Journal of Allergy and Clinical Immunology: 117:326-333. (2006)