What is mold allergy?
An allergy is an abnormal reaction by your immune system to common substances that don’t affect most people. Molds are a type of fungus that exists almost everywhere in the world. The molds that grow inside our houses prefer dark and damp places and can be harmful to some people with immune systems that develop responses against mold.
People with mold allergies may develop itchy skin or rash, watery or itchy eyes, runny or itchy noses or in more severe cases, breathing problems.
There are probably thousands of different types of molds. It’s possible to be allergic to only certain types of mold.
Are there different types of mold allergies?
You can be allergic to molds in the air, and you can be allergic to molds in foods. Some food allergies related to mold include mushrooms, certain types of cheese, fermented foods, some wines and food products that contain vinegar.
There are also many different types of mold that can cause allergies. Some common ones include _Alternaria, Aspergillus, _Cladosporium and Penicillium. There are also toxic molds that can cause very serious illnesses. An example of a toxic mold is Stachybotrys, which is known as “black mold.” In addition to allergies, aspergillus can cause infections known as aspergillosis.
Who does mold allergy affect?
Molds can irritate everyone, regardless of whether you're allergic to them. But the effects are generally worse for certain groups of people who have compromised immune systems due to disease or medication.
Risk factors for developing an allergy to mold include:
- Having a family or personal history of allergies.
- Having a respiratory condition like asthma or chronic obstructive pulmonary disease (COPD).
- Being exposed to mold over a long period of time due to your job or to living in a humid house or a building with poor ventilation.
How common is mold allergy?
According to some statistics, about 1 in 5 people in the U.S. have been diagnosed with environmental allergies. (Mold is considered an environmental allergen.) About two-thirds of people with asthma also have environmental allergies. Many days of work are lost and more than 50% of people who have such allergies consider them to play a part in their quality of life.
Symptoms and Causes
What causes mold allergy?
Molds produce spores. Allergies happen when your immune system is very sensitive to outside substances, such as mold spores. Your body produces antibodies against the mold spores. As you’re repeatedly exposed to the mold spores over time, your body sees the mold spores as something to be destroyed and your immune system creates bigger reactions to protect you.
It’s also possible to allergic to fungi in food, like mushrooms or fermented foods. This type of allergy generally causes local symptoms in the mouth and can cause rashes or even affect breathing.
What are the signs and symptoms of mold allergy?
Mold allergy symptoms and signs resemble those of other types of respiratory allergies and may include:
- Runny nose or nasal congestion.
- Itchy eyes and/or throat.
- Coughing and sneezing.
- Skin rash.
If you have asthma, mold allergies can act as a trigger for an asthma attack. Some types of mold might make you feel like you have the flu, even to the point of having a fever and feeling generally unwell.
Some types of molds can cause even more severe symptoms, like lung infections or anaphylaxis (life-threatening allergy symptoms involving lungs). Other types (like black mold) can produce mycotoxins, which are very dangerous and can even be fatal. Your body can absorb mycotoxins through your airways, skin or intestines.
Severe mycotoxin symptoms include:
- Pregnancy complications.
- Lung scarring (fibrosis) and/or bleeding.
- Diseases of nearly all body systems, including the digestive system, the immune system and the nervous system.
- Problems with the liver, kidneys and blood.
Diagnosis and Tests
How is mold allergy diagnosed?
To diagnose an allergy to mold, your healthcare provider will take a complete medical history and examine you. To diagnose most types of allergies, including mold, your provider will probably do a skin and/or blood test.
The skin test involves scratching your skin with needles that have mold extracts on them. If you’re allergic to the molds, you’ll probably have some type of reaction, like itching or redness or swelling.
Blood tests can provide allergy screening or an allergen-specific IgE antibody test. This can help to diagnose an allergy or to see if treatment is working.
Management and Treatment
How is mold allergy treated?
One of the most important ways to manage a mold allergy is to avoid mold. Reduce your exposure to mold as much as possible by avoiding damp places and things like piles of wet leaves. Make sure your bathroom has an exhaust fan or window you can open to limit dampness and beware of leaks in your roof, walls or pipes in your home.
Your provider might suggest immunotherapy to reduce your sensitivity to mold, commonly known as allergy shots.
Medications, like antihistamines or nasal steroids can give you relief from symptoms. If you have asthma, your provider may suggest a different medication, like inhaled steroids or mast cell stabilizers.
Can mold allergy be cured?
Currently, there’s no way to cure an allergy to mold.
How can I prevent mold allergy?
While you can’t prevent mold allergy from happening, you can take steps to prevent and remove mold.
To keep mold out of your house, you need to control moisture. Take steps to keep the humidity in your house low. Make sure your house is properly ventilated. Repair any water leaks immediately.
If you have mold, you need to clean it up. You can use the appropriate household cleaners or a bleach and water solution of 1 cup bleach and 1 gallon of water. If you do your own mold cleaning, it’s best to wear protective clothing, including gloves and a respirator.
Some mold problems require professional help. These include situations that involve water dirtied by sewage or other contaminants. If you have severe reactions to mold, you shouldn’t do your own cleaning. It’s best to have someone else do the cleaning in this case.
You should throw away any carpets, rugs or other textiles that got wet and weren’t dried right away. Other absorbent items, such as ceiling tiles, also can’t be completely cleaned of mold.
Mold isn’t just an indoor problem. Outdoor mold can also present problems. If mold counts are high, it might be best to stay indoors. Try to keep your yard free of piles of damp and decaying leaves or wood. Check your local mold counts to determine if air quality is safe.
Outlook / Prognosis
What is the outlook for people who have a mold allergy?
Mold allergy can’t be cured, but it can be managed with efforts to reduce your exposure to mold and with taking suggested medications if needed.
There are certain types of molds that are more dangerous to your health than others. These are molds that emit mycotoxins or cause infections, which can cause serious illness and even death.
When should I see my healthcare provider about mold allergy?
If you have symptoms you think are related to mold, call your provider. They can treat your symptoms and may want to do allergy testing.
If you do have asthma or other breathing problems, and you suspect you have an allergy to mold, contact your provider. If you have any type of severe breathing problem, call 911 or go to an emergency room.
If your mold allergy is confirmed, make sure that you follow the instructions of your provider. You may need to carry an epinephrine injector if you have severe reactions to mold. This type of medicine treats life-threatening allergic reactions.
A note from Cleveland Clinic
Allergies are common conditions. If you have them, it means you react differently to certain substances than other people do. The best thing to do is avoid what you’re allergic to. Among people with allergies, an allergy to mold or other environmental substances happens to 1 in 5 people. Many allergic reactions to mold are similar to the types of reactions you have to other allergens like pet dander or dust. You may have itchy eyes or skin, and your nose might run. Some reactions to mold are more dangerous, like when it acts as an asthma trigger. Keep in contact with your healthcare provider to know the best ways to treat your mold allergy.
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