Black Mold Symptoms? What CDC Says

There Is No Black-Mold-Specific Symptom Pattern

CDC says Stachybotrys chartarum and other indoor molds may cause nonspecific symptoms, and no test proves that Stachybotrys caused a particular symptom. Damp or moldy buildings are associated most consistently with respiratory and allergic problems such as:

Respiratory

Coughing and wheezing
Shortness of breath
Nasal congestion
Sore throat
Chest tightness

Allergic Reactions

Sneezing
Runny or stuffy nose
Itchy, watery eyes
Skin rashes or hives
Postnasal drip

Respiratory Symptoms in Detail

Respiratory and allergic symptoms vary from person to person. A visible area or a length of time indoors cannot predict how severe an individual's reaction will be. Clinical context includes:

Your individual sensitivity
Asthma, mold allergy, or chronic lung disease
Immune status and other medical conditions
Other indoor exposures and possible non-mold causes

Asthma and Mold

People with asthma can be more sensitive to damp or moldy environments. Exposure may:

Trigger asthma symptoms or attacks
Make existing asthma worse
Increase coughing, wheezing, or chest tightness in sensitive people
Make prompt moisture correction and an asthma action plan especially important

If you have asthma and suspect mold exposure, see our detailed guide on mold and asthma.

Persistent Sinus Symptoms

Nasal congestion, facial pressure, reduced smell, and discharge have many possible causes. If they persist, ask a healthcare provider for an evaluation instead of assuming black mold is the cause.

Other Reported Symptoms

People sometimes connect headaches, fatigue, dizziness, or concentration problems with a damp building. These symptoms are nonspecific and can have many causes.

Nonspecific Complaints Some People Report

Headaches
Difficulty concentrating ("brain fog")
Dizziness
Fatigue

Irritation and Allergic Symptoms

Eye irritation and redness
Skin irritation or rashes

Who Is Most at Risk?

Some people are more vulnerable to mold-related health effects:

Higher Risk Groups

Infants and young children
Elderly individuals
People with asthma or allergies
Those with weakened immune systems
People with chronic lung diseases
Individuals undergoing chemotherapy

Occupational Risk

Agricultural workers
Construction workers
Mill and lumber workers
Greenhouse employees
Anyone working in damp buildings

Learn more about vulnerable populations and mold.

When to See a Doctor

Get Emergency Help Now

Call emergency services for severe trouble breathing, blue or gray lips or face, chest pain, confusion or fainting, or asthma symptoms that do not respond to your prescribed rescue plan.

Contact a Clinician Promptly

Fever along with respiratory symptoms
Persistent cough lasting more than 2 weeks
Blood-streaked mucus or sputum
Symptoms that significantly worsen at home

What to Tell Your Doctor

When symptoms started
Whether they're worse in certain locations
If others in the household have similar symptoms
Any visible mold or water damage in your home
Your medical history, especially asthma or allergies

For more guidance, see our complete guide on when to see a doctor for mold exposure.

What to Do If You Have Symptoms

Immediate Steps

Reduce exposure: Spend time away from the affected area
Document symptoms: Note when they started and severity
Inspect your home: Look for visible mold or water damage
Check for patterns: Do symptoms improve away from home?

Next Steps

See a doctor if symptoms are severe or persistent
Investigate moisture, damage, or musty odors if building evidence suggests hidden growth
Address any water damage or moisture problems immediately
Don't disturb visible mold—this can spread spores