Share this on:Copied!

When the weather turns humid or damp and the leaves start to fall, you may start to experience mold allergy symptoms. But the fall season isn’t the only time of year you may find yourself dealing with mold allergy symptoms. Here’s what you need to know about molds and how they may harm your health.

What Is Mold?

Molds are a type of fungus found both indoors and outdoors. They can occur almost anywhere that moisture and oxygen exist — and they’re a common cause of allergy symptoms.

Molds are a natural part of the environment and can live and grow in moist places. Outdoors, molds help break down dead organic matter, such as fallen leaves or dead tree limbs. Indoors, mold growth can cause wood rot that may lead to structural damage to your home and trigger allergy and asthma symptoms.

Molds spread by producing microscopically tiny cells called spores that float through the air.

You can’t see individual spores without a microscope. But you can see colonies of spores growing on damp surfaces, such as old leftover food or wet walls.

Too much moisture in your home or in building materials can cause mold to grow. After that, mold spores can continue to grow for years.

That’s according to the U.S. Environmental Protection Agency (EPA). Even if the spores are dead, the protein allergens in and on them can continue to cause allergy symptoms.

Spotting mold growth indoors isn’t always easy. In homes with water damage, mold can hide behind walls and plumbing fixtures.

You might smell mold before you see it. Mold produces microbial volatile organic compounds (VOCs) that often produce a strong, musky smell.

Mold Allergy Symptoms

For many people, breathing in mold spores can trigger an allergic reaction. Some may develop symptoms right away. For others, developing allergy symptoms may take longer.

Even though there are hundreds of types of mold, not all of them cause allergy or asthma symptoms. According to the Allergy and Asthma Foundation of America, the most common allergy-causing molds include:

• Alternaria
• Aspergillus
• Cladosporium
• Penicillium

People who have mold allergies have an immune-system reaction to breathing in specific mold spores. Their body treats these mold spores like an allergen or invader. To fight off an allergen, your immune system releases chemicals that cause symptoms of allergic rhinitis or hay fever, including:

• Congestion or stuffy nose.
• Itchy, red, or swollen eyes or nose.
• Mucus or phlegm in the throat.
• Postnasal drip, which can cause a cough or a scratchy or sore throat.
• Runny nose.
• Sneezing.

When mold spores reach the lungs, they can trigger asthma symptoms. Symptoms of allergic asthma include:

• Chest tightness.
• Shortness of breath.
• Wheezing.

You may notice allergy or asthma symptoms when you’re in a damp or humid room, such as a moldy basement or bathroom. This can mean you have a mold allergy.

Aspergillus fumigatus, a mold found in soils, can cause a serious respiratory reaction called allergic bronchopulmonary aspergillosis (ABPA). People who already have asthma are at a higher risk of developing ABPA. The symptoms of ABPA are similar to those of allergic asthma, but other symptoms can include:

• Cough with bloody mucus or brown flecks.
• Fever.
• Weakness.

Are Mold Allergies Seasonal?

Outdoor air can contain mold spores throughout the year. But different seasons have higher or lower levels, according to the American Academy of Allergy Asthma & Immunology.

Spore levels are lower in the winter when the air is cold and even lower after a snowfall. They’re higher during summer months when the air is warm and moist and even higher after it rains.

The National Allergy Bureau issues alerts to many areas of the U.S. and Canada when pollen and mold spore levels are high. You can sign up for alerts with an NAB station near you.

Diagnosing Mold Allergies

If you have allergy or asthma symptoms, talk to your doctor. Mold allergy symptoms are similar to those of other conditions. Your doctor can refer you to an allergist or immunologist who can find out whether mold is to blame for your symptoms.

The most common way these specialists diagnose mold allergens is through a skin prick test. But your allergist or immunologist may order other tests, if necessary.

Risk factors for mold allergies

Like other allergies, mold allergies can run in families. If either of your parents has any type of allergy, you’re more at risk of developing a mold allergy. But you can also develop a mold allergy even if your parents don’t have any allergies.

How Do You Treat Mold Allergies?

Treatment for mold allergy symptoms is the same as treating symptoms of seasonal allergies. These include:

• Antihistamines.
• Corticosteroid nasal sprays.
• Decongestants.
• Immunotherapy, or allergy shots.

Doctors may treat ABPA symptoms with oral corticosteroids and even an oral antifungal medicine.

Part of mold allergy treatment includes preventing the growth of indoor mold allergens.

Preventing Indoor Mold Allergens

You can’t get rid of every mold spore in your home or other indoor environment. But controlling indoor moisture levels can help you reduce fungal spore levels that trigger allergy symptoms. Follow these tips from the EPA to control moisture levels in your home:

• Clean and dry any damp or wet building materials or furnishings within 48 hours.
• Don’t install carpeting in areas with continual moisture, such as in a bathroom or on concrete basement floors that get frequent condensation.
• Maintain gutters and downspouts to prevent water damage from rain and snowstorms.
• Prevent condensation on cold surfaces like windows and exterior walls by adding insulation to your home.
• Regrade your exterior landscaping to move water away from your house.
• Repair plumbing leaks right away.
• Replace absorbent building materials (such as drywall or ceiling tiles) that have mold growth.
• Wash mold off hard, nonporous surfaces with water and detergent, and then dry them completely.

You can also control mold by limiting the humidity in your house to 30% to 60%. You can do this by:

• Using air conditioners and dehumidifiers.
• Using exhaust fans when cooking or cleaning.
• Ventilating bathrooms and clothes dryers outdoors.

The EPA has tips and techniques for how you can clean up mold yourself and when to hire a professional.