“Black mold” refers to several species of mold (which is a type of fungus) that have a dark green or black appearance. The most common species is Stachybotrys chartarum.

These molds thrive in warm, frequently moist environments, including baths, showers, toilets, kitchens, and basements. They can also grow on wood, dirt, or paper. Mold may grow even more plentifully in humid climates or if you use a humidifier indoors.

Many black molds are toxigenic, meaning that they release toxins that can be irritating or even harmful for people who have preexisting conditions. Called mycotoxins, they’re produced as mold spores eat, grow, and form colonies with other spores.

High concentrations of mycotoxins may cause mold poisoning even in healthy individuals depending on the concentration of mycotoxins, the amount of time exposed to them, and other variables.

Learn how to identify mold poisoning symptoms, how mold poisoning is diagnosed and treated, and how you can cope with and reduce toxic molds in your home.

Mycotoxicosis, or “mold poisoning,” can affect the upper respiratory system with symptoms like those of a cold or flu. Additional symptoms brought on by mycotoxins are especially harmful or even fatal to someone with allergies or asthma.

Common mold poisoning symptoms for those without a respiratory condition include:

  • coughing
  • wheezing
  • nose stuffiness
  • itchy or red eyes
  • itchy skin

If you have allergies or asthma, you may experience more severe forms of these symptoms or have other serious symptoms, such as:

  • headaches
  • feeling exhausted
  • frequent coughing, especially at night
  • sinusitis
  • allergic reactions
  • chest colds
  • fever
  • difficulty breathing

Long-term mold exposure, even if it doesn’t cause immediate symptoms, may also lead to:

  • losing your hair
  • anxiety
  • confusion or memory loss
  • numbness in hands and feet
  • stomach pains
  • sensitivity to light
  • gaining weight for no reason
  • muscle cramps

Mold exposure can cause severe symptoms if you have any of the following conditions:

Mold exposure can be harmful to anyone but especially so to young children. A 2012 study of 36 species of molds in 289 homes with 8-month-old infants found that infants and young children exposed to mold may be more likely to develop asthma later in life.

Mold poisoning can’t always be diagnosed by symptoms alone. Blood tests, allergy tests, and assessments of mold levels in your home may all be needed to specifically diagnose mold-related illness.

To test for mold poisoning or allergies, your doctor may perform one of these tests:

  • Blood test. Your doctor takes a blood sample and sends it to a testing laboratory to test for the reaction of certain antibodies in your immune system to different mold species, including black mold. This can help diagnose both mold allergies and more severe reactions to mold that may indicate mold poisoning. A blood test can also check for biotoxins in your blood from mold exposure, which can also reveal mold poisoning.
  • Skin prick test. Your doctor takes tiny amounts of mold and applies it to your skin using a tiny needle. Your skin will break out in bumps, a rash, or hives if you’re allergic to that mold species.

Treatment for mold allergies and exposure symptoms may include:

  • Nasal sprays or rinses. Over-the-counter nasal corticosteroids, such as fluticasone (Flonase), reduce airway inflammation caused by mold allergies. Shop for Flonase online. Also, a solution of warm, distilled water and saline can help rinse your nasal passages of mold spores and remove congestion.
  • Over-the-counter (OTC) medications. Antihistamines, such as cetirizine (Zyrtec) or loratadine (Claritin), reduce your immune system response, minimizing airway inflammation. Find Zyrtec and Claritin online. Decongestants, such as pseudoephedrine (Sudafed), help keep down swelling due to allergic reactions. Purchase Sudafed here.
  • Montelukast (Singulair). This oral medication reduces mucus in your airways, which reduces symptoms of both mold allergies and asthma. It also increases your risk of severe behavioral and mood changes, such as suicidal thoughts or actions. It should only be used as an allergy treatment if there are no suitable alternatives.
  • Allergy shots. Your doctor may recommend getting regular shots with small amounts of allergens to build up your body’s immunity to them over time.

Take a deeper look at allergy testing and treatments.

It’s best to hire a professional to help you identify and remove black mold, especially if you’re severely allergic or vulnerable to it.

Here are some steps for identifying and removing black mold.

Identifying mold in your home

  1. Look for black, clustered growths, especially in warm, moist rooms. Pay attention to whether you start coughing, sneezing, or wheezing when you enter the room — even if you don’t see mold, the spores or mycotoxins can still cause symptoms.
  2. Look for causes of mold growth, such as a leak, lack of ventilation, or old food, papers, or wood.
  3. Resolve any issues causing mold growth. Throw away anything affected by mold or contributing to mold growth.

Removing mold from your home

  1. Remove any objects from the area that haven’t been touched by mold growth.
  2. Put up plastic sheets on windows and doors to seal the room.
  3. Set up a HEPA air purifier in the room to capture mold spores. You can find a selection of HEPA air purifiers here.
  4. Cover yourself with a mask, gloves, boots, and a mold-resistant suit. Purchase protective masks online.
  5. Cut away and replace mold-damaged drywall from the room full of mold.
  6. Cover nonporous surfaces affected by mold with bleach or a fungicidal agent.
  7. Let these areas dry before you renovate the room.

Here are some do’s and don’ts for keeping mold from growing indoors.


  • Clean and vacuum your home regularly.
  • Leave doors and windows open for ventilation when you bathe, shower, or do other activities that can increase moisture.
  • Use a dehumidifier to keep indoor relative humidity (RH) below 50 percent. Browse a selection of dehumidifiers here.
  • Use an indoor air purifier with high-efficiency particulate air (HEPA) filtration or install an appropriate high-efficiency filter in your furnace or ventilation system.
  • Make sure your rain gutters are clean and not blocking water drainage.


  • Don’t leave old books, newspapers, or wood sitting unused for long periods.
  • Don’t put carpet in rooms like bathrooms, kitchens, and basements.
  • Don’t ignore leaks from pipes or groundwater—fix them as soon as possible.

People with asthma, allergies, or immune system conditions are especially vulnerable to mold.

But it’s not difficult to prevent mold overgrowth by keeping your indoor humidity low and your space clean.

Keep an eye out for small growths and do something about mold before it grows out of your control.

If you think your health is being affected by mold exposure, speak to your doctor or allergist.