Mould Illness Causes, Symptoms and Health Issues

Mould Illness And Symptoms

Mould is a fungus that you can find both inside and outside, and there are thousands of different species. Mould can thrive in any environment that is humid, damp and warm, and it spreads by producing small spores that float through the air. 

Exposure to mould on either a long-term or short-term basis can lead to mould illness. This isn’t an allergic reaction to the mould. Instead, it’s an inflammation that spreads throughout your body because your immune system overreacts to the presence of mould spores. Formally, this illness falls under the category of a biotoxin illness, better known as Chronic Inflammatory Response Syndrome.

Now that you know what mould is, we’re going to dive in depth into the symptoms, causes and health issues people who have mould illness can face. Our goal is to give you a good understanding of what to watch for if you live in an area where mould is common.

Mould Illness Causes

When mould starts to grow, it produces irritants and allergens. You can inhale the mould spores to set off a reaction. Touching the mould and then touching your face is another way to come into contact with the mould. One of the most common reasons people develop health problems due to mould is exposure to water-damaged buildings.

These buildings are perfect breeding grounds for harmful bacteria, fungi, mycobacteria and more. This toxic breeding ground creates an environment that is very hard on your body, and it makes you more prone to infection. Several things that make water damaged buildings home and could cause you to experience the system-wide inflammation that comes with mould illness include: 

  • Actinomycetes
  • Bacteria
  • Beta Glucans
  • Endotoxins
  • Fungi
  • Hemolysins
  • Inflammagens
  • Microbial Volatile Organic Compounds (VOCs)
  • Mould
  • Mycobacteria
  • Mycotoxins
  • Spores

Mould Illness Symptoms

Mould illness symptoms can vary from person to person and in severity. Additionally, a person may only experience one or two of the common mould illness symptoms while other people experience them all. Mould illness symptoms include:

  • Fatigue and Weakness – One hallmark symptom of mould illness is fatigue. Your body exhausts itself when your immune system sends out system-wide inflammation to combat the infection or illness. This drains your body, and you become fatigued and experience generalised weakness as a result.
  • Mental Status Changes – Continued exposure to mould can cause mental status changes. It’s common for people to experience trouble concentrating, trouble learning new things, difficulty remembering people or events, generalised confusion and disorientation.
  • Body Temperature Regulation Issues– The system-wide inflammation can often come with increased body temperature or difficulty regulating your temperature. It’s common to experience chills and night sweats.
  • Excessive Thirst and Increased Urination – You could find yourself being excessively thirsty even if you drink constantly. As you drink more, you’ll have increased urination because your body tries to flush the excess water out of your system.
  • Tremors– Certain strains of mould are neurotoxic. This means that they can kill neurons in your brain, and this can result in impaired mobility or tremors in your extremities. It can get worse as the mould illness progresses.
  • Metallic Taste – Many people report a distinct metallic taste in their mouths, and this is due to the mould disrupting and damaging the nerve cells that have links to your taste buds. The metallic taste can linger in the back of your throat for days or weeks.
  • Headache and Light Sensitivity– The system-wide inflammation can cause your blood pressure to spike, and this can cause headaches or migraines. As this progresses, you could have light sensitivity that can make your migraines or headaches worse.
  • Gastrointestinal Issues– Many people have abdominal pain, cramping, diarrhoea, appetite changes and other gastrointestinal issues. These issues tend to resolve as they treat the mould illness and eliminate the exposure.

Health Issues Caused by Mould Illness

Long-term exposure to mould can lead to long-term health issues. These health issues have the potential to get worse as your body tries and fails to fight the mould infection. Again, not everyone will experience the same health issues, but possible concerns include:

Allergic Reactions

  • One of the most common health issues for people with mould illness is an almost constant state of allergic reaction. This can range from mild problems like itchy eyes, sneezing and irritation to more severe issues like swelling of the throat and difficulty breathing. People who have these reactions may try to medicate with their allergy medicine, but removing the mould is the best route.


  • Mould can trigger asthma symptoms and general inflammation that doesn’t go away. Wheezing, coughing, respiratory tract inflammation and having difficulty catching your breath are all hallmark symptoms of having an asthma flare or an asthma attack. Additionally, people with asthma are generally more sensitive to irritants like mould, so this can increase symptom severity.

Bronchitis and Pneumonia

  • Bronchitis and pneumonia are types of respiratory tract infections that can develop when you breathe in mould spores. Your airway and lung lining will start to produce a layer of mucus and swell to try and remove the mould spores. You’ll also cough more in an attempt to remove the mucus, and fluid can build up and make it difficult for you to breathe. 

Why You Should See a Doctor

You can only get a proper diagnosis of mould illness by visiting your doctor. There are medical professionals who specialise in the diagnosis of mould illness. The important first step in recovering from mould illness is to remove yourself from the mouldy environment.