The word mold surrounded by a stethoscope.

We’ve all been there — scratchy throat, watery eyes, sneezing and coughing. Allergies are no fun, and identifying their source can be a little tricky. Is it ragweed? Seasonal pollen? Hay fever? Fluffy the cat?

Or could it be the mold lurking in the darker recesses of your home?

According to the Cleveland Clinic, about one in five people have a mold allergy, meaning that if you or someone in your family have inexplicable allergic symptoms, mold might be to blame.1 We’re going to unpack everything there is to know about mold allergies here, but first, let’s start by discussing the culprit itself.

What Is Mold?

“Mold” is actually an umbrella term that refers to any sort of fungal growth that can appear on decaying organic matter. Molds spread by releasing tiny reproductive cells called spores that are invisible to the naked eye.2 More on this later, but it’s these spores that actually cause allergic reactions in some people.

FYI: Mold has been around for a long, long time. The first fungi evolved about a billion years ago. That means keeping mold out of our homes has been an issue as long as humans have had homes.3

Even if you keep the cleanest home imaginable, you and your family will still be exposed to mold in some form or fashion. There are steps you can take to mitigate that exposure, of course, but for adults and children who have asthma or are otherwise high-risk, avoiding mold should be a priority.

Why Are Some People Allergic to Mold?

There’s no real scientific consensus on why some people develop allergies and others don’t. Studies do reveal, though, that it comes down to two factors: your environment and your genetics.4 While you can’t really control your genes, you can — for the most part — control your environment. Making sure your exposure to mold in your home is limited can be a chore, but it’s well worth it if you or your children are sensitive.

FYI: When it comes to allergies, you need to pay careful attention to your young children. Allergies are particularly common in kids, although they might go away as the child ages.5

But what do we mean, exactly, by allergies? An allergy is an abnormal reaction of your immune system to an environmental factor. Essentially, your body overreacts to some foreign element introduced to it — in this case, mold spores. Your body recognizes the spores as a threat that needs to be destroyed and your immune system kicks into high gear to protect you.6

What Are the Symptoms of a Mold Allergy?

Unfortunately, it’s difficult to pinpoint exactly what’s causing your allergic reaction. Mold allergies present in the same way as most upper respiratory allergies.7 This can include:

  • Sneezing
  • Runny or stuffy nose
  • Itchy eyes and throat
  • Cough
  • Postnasal drip
  • Watery eyes
  • Scaly skin

Now that doesn’t sound like any fun, but for the most part, mold allergies aren’t all that serious. When they do become a major problem, though, is when the person experiencing them is very young, very old, or has another respiratory condition like asthma.

If you have young children in the house or take care of older relatives, it’s important to pay attention to any allergies they might have. That’s doubly true if they have comorbidities (two or more diseases or medical conditions). Severe allergic reactions called anaphylaxis can occur. These serious symptoms can include:

  • Feeling lightheaded or faint
  • Increased heart rate
  • Difficulty breathing
  • Wheezing
  • Confusion
  • Loss of consciousness

If allergic reactions persist or worsen over time, it’s best to see a doctor. More on that in just a bit. First, let’s talk about the types of mold that might cause allergic reactions.

What Types of Mold Cause Allergies?

As we discussed in our guide to the most common types of household mold, there are three categories of mold — allergenic, pathogenic, and toxigenic. Obviously, pathogenic and toxigenic molds are more dangerous, with the ability to cause specific diseases like pulmonary histoplasmosis or cryptococcal meningitis or lead to paralysis, convulsions, or in extreme cases, death.9

FYI: Extreme reactions to mold are very rare, especially in folks that have healthy immune systems. If your allergic reactions are frequent and severe, there’s a good chance mold isn’t the culprit.

Luckily, those molds are fairly rare, and you’d likely need to be exposed to high quantities over long durations to feel the worst effects. Much more common are the allergenic molds, which, as we said above, aren’t all that threatening for most families.

The three most common types of allergenic molds in households include Cladosporium, Penicillium, and Aspergillus.10 They typically grow in dark, moist areas where they have organic matter to consume. Think crawl spaces, bathrooms, underneath the sink, and near your HVAC units. Penicillium in particular tends to grow on food. You know the green stuff that grows on the leftover Chinese food you forgot about for a few weeks? That’s probably Penicillium.

It’s difficult to identify what type of mold you’re dealing with, as different types of molds can grow together, and their presentation depends heavily on the surface on which they’re growing. However, here’s what to look out for with the three we mentioned above:


Name: Aspergillus
Categorization: Allergenic
Appearance: A black surface with a white or yellowish base
Found on: Dead leaves, soil, grain — think houseplants, crawl spaces, and gardens


Name: Cladosporium
Categorization: Allergenic
Appearance: Black, green, or brown spots
Found on: Damp, building materials like gypsum board, acrylic painted walls, wood, wallpaper, carpet, and insulation


Name: Penicillium
Categorization: Allergenic
Appearance: Blue-green, fluffy outcroppings
Found on: Food, mostly


As mentioned, these molds aren’t necessarily dangerous unless exposure is prolonged. Making sure your house is tidy, plenty of ventilation, and water is cleaned up promptly will likely prevent these molds from growing in quantities that would cause allergic reactions. That said, we should talk about dangerous molds.

What Are the Most Dangerous Types of Mold?

Pathogenic and toxigenic molds need to be taken seriously and will likely need to be removed by professionals. Cryptococcus neoformans, which is found most commonly in damp, building materials, and certain strains of Aspergillus qualify as pathogenic. This means they can cause severe, even life-threatening symptoms and disorders.

FYI: In order for mold allergies to progress into the “dangerous” territory, you or your loved one must be hypersensitive, or have prolonged exposure to large quantities of mold.

Aspergillosis is one of these. Most commonly caused by certain strains of Aspergillus fungus, this disease can cause coughing, wheezing, fever, chest pain, general malaise, and difficulty breathing. It can also lead to kidney or liver failure in some cases. Luckily, Aspergillosis is unlikely to occur in folks with healthy immune systems, but those with chronic lung problems or weakened immune systems are at higher risk.11

Even more dangerous is Stachybotrys chartarum. More commonly known as black mold, this specific fungus is toxigenic, meaning it will likely have negative health impacts on anyone who interacts with it who doesn’t take the necessary precautions.

Now, let’s take a minute to discuss black mold, because not a whole lot of people understand it or the threats it actually poses.

Can Black Mold Hurt Me or My Family?

So-called black mold gets a bit of a bad rap, mostly due to misunderstandings about its danger. Stachybotrys chartarum is a common type of black mold that produces toxic chemicals that are found in its spores and fragments of the fungus itself called mycotoxins.

These toxins are very harmful if consumed, and can be dangerous if inhaled — particularly for people already sensitive to molds. But there is little evidence to support the fears over so-called “toxic mold syndrome.” There is no proof that limited exposure to Stachybotrys chartarum — or any other common household mold for that matter — can cause extreme or life-threatening symptoms in otherwise healthy individuals.12

Pro Tip: Black mold thrives in damp areas rich in cellulose. That means if your stack of recyclables gets rained on, it’s a prime habitat. Remember, mold needs moisture and “food” to survive.13

Now, let’s take what we just said and put it into proper context. It’s very difficult for a layperson to determine what kind of mold is growing in their home just by looking at it, so every mold bloom should be taken seriously. In large quantities and over extended amounts of time, mold can absolutely cause negative health outcomes, so if it shows up, it needs to be addressed promptly and appropriately.

Sometimes mold removal can be done by donning the proper protective equipment and using the appropriate cleaners to remove the mold. Other times it means calling in professional mold remediation specialists.

So understanding the threats molds pose to you and your family is all well and good, but in the meantime, you’ll need to deal with the symptoms of your allergies.

What Should I Do If I’m Experiencing Mold Allergy Symptoms?

If you or your loved ones are experiencing mold allergy symptoms, the treatment will likely be the same for any other type of upper respiratory allergy. Symptoms usually appear a few hours after exposure and can last for up to three days in people with mold sensitivities.

Pro Tip: Cleaning out cluttered areas like basements and garages can disturb mold blooms. Make sure you’re wearing the proper protection when engaging in these activities, including gloves and masks.

Over-the-counter medication will likely be enough to manage symptoms. Oral decongestants, antihistamines, and nasal sprays are all appropriate to use in response to a mold allergy. However, it’s always best to check with your doctor before using medications you’re unsure of. In severe cases, you might require an allergy shot.14

If readily available medications don’t do the trick, you might need to seek the help of medical professionals.

And if the mold infestation is significant enough, you might need to consider relocating while you call in professional mold remediators to do their work. Remember, at-risk family members like older seniors and young children will be especially vulnerable and could experience more severe allergic reactions to mold than you might.

What if My Symptoms Worsen?

There is a small chance that exposure to mold over time can cause hypersensitivity pneumonitis.15 HP is a type of lung inflammation that occurs when folks develop immune system sensitization, which is similar to an allergy. This mimics the symptoms of pneumonia but doesn’t respond to antibiotic treatment. These symptoms can include:

  • Shortness of breath
  • Muscle aches
  • Severe cough
  • Night sweats
  • Fever
  • Profound fatigue

Before you get too worried, though, it’s important to note that HP typically occurs in folks who work in environments where they are exposed to high levels of mold and organic particulate matter. (To give you an indication of  who generally contracts it, it’s also called “bird breeder’s lung” or “mushroom picker’s disease.”) Simply put, it’s unlikely that the smattering of mold you find under your kitchen sink is going to cause HP.

That said, if your or your family member’s symptoms persist or worsen, you should definitely talk to a professional.

Are There Mold Allergy Specialists?

Your primary care provider will likely be your first stop if your or your family member’s symptoms are prolonged or profound. If necessary, they will likely refer you to an allergy and immunology specialist, or a pulmonologist. Here’s what those doctors do:

  • Allergy and immunology specialist. This discipline involves the management of disorders related to the immune system, gastrointestinal disorders, skin-related allergic conditions, and adverse reactions to certain foods. They also address systemic diseases and diseases associated with autoimmune responses.16
  • Pulmonologist. This discipline deals specifically with lung conditions and diseases of the respiratory system, including the nose, throat, trachea, and airways.17

These specialists treat a whole host of diseases and disorders associated with all types of allergies, including mold. If your or your family member’s symptoms are severe enough, it’s a good idea to get in touch with a specialist.

Final Thoughts on Mold Allergies

While nothing can be done to cure a mold allergy, per se, there is plenty that can be done to prevent these from negatively impacting the quality of life for you or your family members. This might be as simple as taking over-the-counter medications, or it might require talking to a specialist.

Overall, one of the best things you can do to mitigate the negative impacts of mold allergies is to limit you and your family’s exposure. Make sure your home is clean, fix any leaky pipes or fixtures, and keep the relative humidity low. If small amounts of mold are ever discovered — and hey, they will be — clean it thoroughly and remove any factors that will allow it to grow back again. Vigilance is your best friend in the fight against mold.

Household Mold FAQs

What is the best medicine for a mold allergy?

For most people, over-the-counter decongestants, antihistamines, and nasal sprays will do the trick. Others with more severe allergic reactions might need to seek professional medical advice.

What causes mold allergies?

Allergies occur when your body’s immune response goes a little haywire in response to a foreign material. In the case of mold allergies, the spores — which are most commonly released when the mold is disturbed — cause the reaction.

Am I allergic to mold?

It can be difficult to determine what, exactly, is causing an allergic reaction. For more insight, you’ll need to discuss your allergy with your general care practitioner or a specialist.

Can mold trigger asthma attacks?

Yes. Mold is especially dangerous to people with chronic respiratory problems like asthma. If you or a loved one is afflicted, special care must be taken around mold.

Can black mold kill you?

While specific types of black mold are toxigenic, for the most part, they aren’t significantly more dangerous than other types of mold. That said, any mold bloom should be removed upon discovery, and precautions should be taken during the process.