Mold Allergy
By Andy Nish, MD

Molds come under the broad category of fungi, which also includes yeasts. Certain molds that grow on vegetable and other material are referred to as mildew. People can be allergic to all of these and for the rest of this article we will simply refer to mold allergy.

It is the seeds, called spores, released by the fungi which contribute to mold allergy. These spores can be measured in the environment in various ways. Scientists estimate that mold spores may be the most abundant natural particles in outdoor air, although that can vary by season, weather and region. Mold season is typically the worst from spring to late fall, but in the warmest areas of the country exposure and symptoms may be year-round. It is important to realize that there are many molds that may cause an allergic reaction and they will vary by region of the country.

Types of molds
Some of the most common spores found outdoors are those of Alternaria, Cladosporium, and Hormodendrum, and can be found in higher levels with cutting grass, spreading mulch, and in areas with field crops such as grains.

Common indoor molds include Aspergillus and Penicillium. Some molds, such as Epicoccum, Fusarium and Bipolaris are found both indoors and outdoors.

Mold allergy is not related to any reported toxic effects of molds, which has been a recent hot topic with limited scientific evidence. Mold allergy is also not related to any type of infection by molds or fungi.

Mold allergy symptoms
The symptoms of mold allergy show up primarily in the respiratory tract, with nasal symptoms and chest symptoms in some cases. Common symptoms include:

• Sneezing
• Nasal congestion
• Clear runny nose
• Itchy watery eyes

Mold allergies can also trigger asthma, with symptoms of wheeze, cough and shortness of breath. Mold allergy is best diagnosed through skin testing by an allergist/immunologist. When skin testing is not able to be done, blood tests may help with the diagnosis of mold allergy.

Mold avoidance
Typical outdoor situations where mold allergy may be triggered include:

• Being near heavy vegetation
• Being near hay and straw
• Raking leaves
• Cutting grass
• Going outside after a rainstorm

Indoor exposure to mold may be increased in:

• Basements
• Crawl spaces
• Spaces with indoor humidity that is greater than 50%
• Carpeting in bathrooms and kitchens

Mold avoidance measures include:

• Wearing a filter mask if exposure is anticipated
• Eliminate any source of excess dampness in basements
• Consider a dehumidifier
• Try to keep indoor humidity levels between 40% and 50%,
• Change filters regularly
• Make sure there is adequate air circulation
• Clean washable surfaces with a bleach solution

Treatment
Medical treatment for mold allergy includes medicines, such as antihistamines and nasal sprays, which tend to be very effective. For persistent or severe symptoms, immunotherapy or (allergy shots) help to desensitize or decrease the body's allergy to molds in appropriately selected patients. There are a lot of aspects to mold allergy, and good ways to evaluate and handle it. Your allergist/immunologist can help sort out your best options for diagnosis and treatment. To locate an allergist/immunologist in your area, please visit the AAAAI Physician Referral Directory .

This feature was edited by Stuart A. Friedman, MD, FAAAAI, AAAAI Patients & Consumers Web Editor on 3/18/04.