The Ultimate Guide to Mold Allergies

Table of Contents

Do you wake up with a stuffy nose and a sore throat regardless of the season, even though you’re meticulous about cleanliness? Do you feel physically unwell at home but inexplicably better a short while after walking outside?

You might be suffering from a mold allergy.

As with many allergies, a mold allergy can go from being a minor annoyance to a serious sickness.  I lived with this ailment for most of my 20s and I was constantly in and out of doctors’ offices trying to diagnose the issue.

In this guide, you’ll learn everything you need to know about preventing and managing mold allergies. Here’s a quick look at what mold is first.

What Is Mold?

Mold s a multicellular type of fungus. It consists of spores, which are single cells waiting for the right condition to grow. Mold spores can travel in the air and can stick to clothes or animal fur.

These airborne spores are small enough to be inhaled through the nose and into the lungs, which can cause a host of respiratory and health issues.

Mold can look fuzzy and dusty or like a stain. It can also be invisible. Visible mold can be white, greenish, blackish, or a variety of colors.

Mold is a natural decomposer. Some kinds can cause serious illness, while others play an important role in food science and biotechnology. Some, like mushrooms, are even a famous addition to many dishes.

Mold can be found anywhere in a damp environment. It can exist in the dust, in air, on surfaces, indoors and outdoors.

Some types are extremely resistant to extreme weather. Most molds can’t grow in temperatures less than 39℉, which is the temperature at which food is generally refrigerated.

Types of Harmful Mold

There are thousands of mold types. Only a few dozen cause allergies. An allergy to one kind of mold doesn’t necessarily mean an allergy to all other kinds.

Below you’ll find the most common indoor types of molds that cause allergies. Regardless of type, it’s important to eliminate and prevent all kinds of mold growing in your home.


Considered the most dangerous type of mold, Stachybotrys is a greenish-black mold that grows on high-cellulose material, such as wallpaper, ceiling tiles, and insulation material.

Stachybotrys grows where there’s standing water. This can be caused by condensation, water leaks, water infiltration, flooding, or any kind of water damage.

Stachybotrys spores release mycotoxins that can trigger and worsen asthma and cause a host of allergic reactions.


Cladosporium mold is a common type of mold that can grow indoors and outdoors. It can be invisible, or it can look brown or green or a spotty black.

Like all molds, Cladosporium likes standing water and warmth. It can be found in damp areas of the house, such as carpets, walls, windowsills, floors, and HVAC vent covers. It can also be found near heating and cooling appliances.

Not everyone is affected by Cladosporium. Symptoms can vary from common allergic reactions like sneezing, coughing, or a stuffy nose to an asthma attack or allergic fungal sinusitis. Different people can show different symptoms.


A major and economically important fungus, Fusarium can be found all over the world in the soil and on plants. Most of its species are harmless, but some are toxic to plants and can cause extensive damage to crops.

Several species can cause infections to humans and severe structural damage to buildings. As long as they can find wet conditions, they can grow rapidly.

Fusarium can look flat or cottony. It can range in color from white, yellow, and lavender to red or purple, or anywhere in between.

Some strains of Fusarium are controversially considered edible, even though people who consumed them complained of debilitating allergic reactions.


Alternaria mold is a common outdoor and indoor mold. It causes diseases and damage to plant leaves, and its spores are airborne.

Like all other molds, it likes humidity and warmth. It can grow on and inside walls, under carpets and floors, and on clothes.

People who are most vulnerable to Alternaria mold are those who already suffer from severe allergies or have weakened immune systems or asthma. Alternaria-contaminated grain is thought to cause oesophageal cancer.


Penicillium is another extremely common fungus that can be found all over the world. It was used to produce penicillin, the first modern antibiotic in the world.

A rapid grower, it emits a powerfully musty odor. Its texture can be velvety or powder-like. It can range in color from blue-green to pink, yellow, and white.

Penicillium can commonly trigger allergies, such as hay fever and hypersensitivity pneumonitis. It can also trigger or worsen asthma.

Penicillium can be found anywhere, from soil to air to people’s homes. Some types of Penicillium produce toxins that spoil food, so it’s recommended to throw out any food that starts to show signs of mold growth.

Mold Allergy Prevention

What Is a Mold Allergy?

If you inhale mold spores and experience an allergic reaction, you probably have a mold allergy.

Unlike hay fever and other seasonal allergies, mold allergy can happen throughout the year since mold is pretty much everywhere.

What Are the Symptoms of a Mold Allergy?

Mold allergy symptoms are quite similar to symptoms caused by other allergies. Here’s a list of the most common reactions to breathing mold spores:

  • sneezing
  • coughing
  • stuffy, runny, or itchy nose
  • itchy or watery eyes
  • sore throat
  • wheezing
  • dry or scaly skin
  • triggered or worsening asthma

Symptoms can happen right upon exposure and can continue all day. They’re usually worse in damp parts of your house with poor ventilation, like your basement or bathroom.

Not all symptoms look like allergy symptoms. One famous symptom is sick-building syndrome, also known as building-sickness syndrome, although it can also be caused by other issues.

If you keep feeling physically unwell when you’re inside your home or office building and remarkably better when you’re outside, you might have a mold allergy because of mold in your home or workplace.

Possible Complications

Severe mold allergies can worsen asthma in people who already suffer from it. They can also cause a number of other complications.

Allergic Bronchopulmonary Aspergillosis

In rare conditions, mold allergy can turn into a serious illness called allergic bronchopulmonary aspergillosis or ABPA. ABPA is an exaggerated response of the immune system. It can affect the airways and damage the lungs permanently.

Especially at risk for ABPA are people with asthma or cystic fibrosis. ABPA can cause violent wheezing and coughing and severe difficulty breathing.

Hypersensitivity Pneumonitis

Hypersensitivity pneumonitis or extrinsic allergic alveolitis is a rare disease of the lungs. It causes inflammation of the lungs because of an allergic reaction to breathing in dust, molds, or chemicals.

Allergic Fungal Sinusitis

Allergic fungal sinusitis is a common allergic reaction that affects the sinuses. It happens when an immunocompromised person breathes in mold or another allergen. Thick fungus builds up until the infected sinus is blocked.

This complication can trigger asthma and can cause nasal polyp growth.

It’s extremely important to diagnose and treat this. Otherwise it can cost patients both their vision and their sense of smell.

Mold-Triggered Asthma

Asthmatics who are allergic to mold can experience asthma flare-ups if they breathe in mold spores. It’s recommended to have an emergency plan in case of a severe asthma attack.

How Do Doctors Diagnose a Mold Allergy?

Typically a doctor will take the patient’s full medical history. A good idea is to keep a diary of your symptoms, so you don’t forget any when speaking with your doctor.

After that, your doctor will run a number of tests. Some doctors may want to rule out other types of allergy or ailment.

Usually, a doctor will prick or scratch a patient’s skin with different fungi extracts. If there’s no reaction, the patient probably has no mold allergy. The doctor may also run allergen-specific IgE blood tests.

Finally, your doctor will consider your medical history together with the skin test and blood test results to make a diagnosis.

How Do You Treat Mold Allergies?

Like any allergy, mold allergy is uncurable. However, you can alleviate and control your symptoms.

Preventing exposure to mold and removing any existing mold are the most important measures you can take.

Some common over-the-counter medications can also help. It’s always important to check with your doctor first.


Here are some common over-the-counter medications for mold allergy symptoms:

  • nasal steroids
  • nasal rinses
  • nasal decongestant pills or sprays
  • antihistamines
  • eye drops

Your doctor may also prescribe an allergy shot or allergen immunotherapy.


There are a number of ways to prevent your exposure to mold.


If you regularly engage in any activity around plants, make sure to wear gloves and a mask, so you don’t breathe in any spores.

Avoid unnecessary outdoor activities when the mold count tends to peak. In colder climates, this spans the period from late winter through early fall. In warmer climates, mold spores can exist in the air throughout the year.

Your goal here is to limit your exposure to mold spores and also to limit the mold spores you end up bringing back home with you.


Unless your allergic reaction is severe enough to warrant moving, here’s a number of measures you can take to prevent mold growth inside your home:

  • Clean your house often
  • Keep your surfaces dry
  • Inspect common mold-growth areas frequently
  • Eliminate standing water by fixing leaks and cleaning spills
  • Ensure your rooms are properly ventilated
  • Get a hygrometer to measure indoor humidity
  • Consider investing in a dehumidifier or air purifier for mold
  • Immediately replace anything that has started growing mold
  • Consider mold-resistant replacements where possible
  • Avoid carpeting damp areas of your home
  • Regularly inspect your gutters
  • Regularly clean refrigerator drain pans and trash cans
  • Improve airflow through your house
  • Use central air conditioning
  • Clean humidifiers, air conditioners, and dehumidifiers
  • Use an exhaust fan or keep your bathroom window open during showers
  • Regularly scour sinks and bathtubs


In many cases, mold will have dug deep into your wall cracks, floor tiles, or other surfaces by the time you discover it.

Removing mold yourself can be risky. It’s recommended to leave the removal of mold to professionals, especially if you’re having an allergic reaction, are asthmatic, or you’re pregnant.

If you decide to tackle the job yourself, make sure you’re wearing the appropriate protective gear.

When to See a Doctor

If over-the-counter medications offer no relief or your symptoms start getting worse, you should see a doctor. Ideally, you’ll be referred to an allergist, who’ll try to determine whether or not you have a mold allergy.

It’s important to see a doctor if you experience any of these symptoms:

  • Severe wheezing
  • Extreme difficulty breathing
  • Cough with brown or brownish spots or bloody mucus

What Foods to Avoid If You Have a Mold Allergy

Certain foods are safe and edible despite containing mold, such as blue cheese. Penicillium Roqueforti and Penicillium Glaucum are the blue molds used in making this type of cheese. Both molds are perfectly safe to eat, because they can’t produce any toxins in cheese.

If you have a mold allergy, however, here’s a somewhat extreme measure that may help your symptoms improve: If you’re up for it, try eliminating foods containing mold and yeast for at least four weeks.

After that, you should start gradually re-introducing each of the foods you cut out of your diet at a time. Documenting your reactions to each is a good idea. This can help you pinpoint the culprits behind your allergic reaction.

Here are some of the more common foods that contain mold:

  • cheese
  • mushrooms
  • foods containing yeast
  • sour cream
  • buttermilk
  • potatoes
  • soy sauce
  • vinegar
  • sauerkraut
  • pickled or smoked meats and fish
  • dried fruits
  • raw vegetables and fruits


For those of us who suffer from asthma and seasonal allergies, it’s easy to feel overwhelmed by a mold allergy on top of all that. After all, mold is everywhere and seems practically impossible to avoid.

Don’t let that bring you down. Stay on top of your cleaning and use a dehumidifier if you live in a humid climate. Call a specialist if you see visible mold. This way, you can breathe easily knowing you’ll nip any moldy problems right in the bud.

Share on facebook
Share on twitter
Share on pinterest
Share on whatsapp
Share on email
Share on print

Leave a Comment

Your email address will not be published. Required fields are marked * Protection Status Scroll to Top