Can Fungus Gnats Bite?
No, fungus gnats do not bite people. These tiny gnats are primarily nuisance pests that feed on decaying organic matter, fungi, and plant roots—not blood or skin. Their mouthparts are designed for feeding on soft plant tissue and fungi, not for piercing skin like mosquitoes or biting flies.
People sometimes mistake the itching or irritation from other small insects (such as biting midges or no-see-ums) for fungus gnat bites because fungus gnats are often seen hovering around indoor plants or damp areas at the same time. However, any redness or itching in such cases is due to another source, not the fungus gnats themselves.
Do Fungus Gnats Bite?
Fungus gnats don’t actually bite, but people often think they do in certain situations where these insects are present and other irritations occur. The perception of being bitten usually happens in environments where fungus gnats are abundant and other small, biting insects may also be present. Here are the situations most likely to make people think fungus gnats are biting:
Around overwatered houseplants or damp soil – Fungus gnats breed in moist, organic-rich soil. When disturbed—such as during watering or plant maintenance—they may swarm around your hands and arms. Their hovering and landing can feel irritating, leading some to believe they’re being bitten.
In humid indoor spaces – Bathrooms, kitchens, or basements with high humidity and poor ventilation can attract fungus gnats. When they fly near exposed skin, their light touch can mimic the sensation of a small bite.
When other tiny biting insects are present – Homes with drain flies, biting midges, or no-see-ums may have overlapping infestations. Because fungus gnats are more visible, people often blame them for bites actually caused by other species.
After prolonged exposure – Continuous gnat activity around the face, eyes, and scalp can lead to minor skin irritation from frequent contact, dust, or allergic responses, which may be mistaken for bite reactions.
In greenhouses or plant-heavy offices – Large numbers of fungus gnats can accumulate in these environments. Their constant buzzing and landing on skin can cause discomfort and the false impression of biting.
In every case, the irritation isn’t from a true bite—fungus gnats lack the anatomy to pierce skin. Managing excess moisture, replacing infested soil, and using traps can prevent these misunderstandings by controlling the source of the infestation.
Fungus Gnat Bites
There are no direct health risks associated with fungus gnat “bites,” because fungus gnats cannot bite or sting. Their mouthparts are designed for feeding on decaying organic matter, fungi, and plant roots—not human or animal tissue. Any irritation people attribute to “fungus gnat bites” comes from other causes, such as:
Skin irritation from contact or allergens – Although fungus gnats don’t bite, their presence in large numbers can cause minor annoyance. In sensitive individuals, repeated contact or exposure to decaying organic material where gnats breed might trigger mild allergic reactions or skin irritation, but not true bite marks.
Misidentified insect bites – It’s common to confuse fungus gnats with other small biting insects, such as biting midges, no-see-ums, or mosquitoes. These pests can cause itchy, red welts or localized swelling, but fungus gnats themselves are harmless.
Plant and soil risks – While they don’t pose a threat to humans or pets, fungus gnat larvae can damage the roots of indoor plants. Heavy infestations can stunt plant growth, cause yellowing leaves, and make plants more susceptible to disease.
In short, the main “risk” of fungus gnats is nuisance and plant damage, not harm to people. If you’re noticing irritation on your skin and suspect fungus gnats, it’s best to investigate for other biting insects while addressing moisture or soil conditions that allow gnats to breed.
What Do Fungus Gnat Bites Look Like?
Fungus gnats do not actually bite, so there are no true fungus gnat bites to identify. If you notice red marks, itchy bumps, or small welts after seeing fungus gnats, those symptoms are being caused by something else—most likely another small biting insect or an unrelated skin irritation.
Here’s how this confusion often happens:
Mistaken identity – Fungus gnats are commonly found in the same areas as other tiny flying insects, such as biting midges (no-see-ums) or mosquitoes, which do bite and leave visible welts. Because fungus gnats are more noticeable, they often get blamed for the marks.
Contact irritation – When fungus gnats land on skin, especially in sensitive areas like the face, scalp, or arms, their movement can feel ticklish or itchy. Scratching afterward can cause mild redness that might look like a bite, even though no puncture occurred.
Allergic or environmental reactions – Itchy spots or small rashes around areas where fungus gnats are active may actually result from contact with plant material, mold, or fungus in damp soil where they breed—not from the insects themselves.
If you’re seeing marks on your skin and suspect fungus gnats, take a close look at your surroundings. Check for other biting insects (like no-see-ums, fleas, or mosquitoes), and inspect plant soil for moisture problems. Fungus gnats are harmless to people, but managing excess moisture and organic buildup will help eliminate both the gnats and the potential sources of skin irritation nearby.
What To Do About Fungus Gnat Bites
If you think you’ve been bitten by fungus gnats, the good news is that they can’t actually bite, so any skin irritation you’re experiencing is coming from another source—such as a different insect, an allergic reaction, or contact with something in your environment. Here’s what you should do to address both the irritation and the pest issue:
Treat the skin irritation
Clean the area with mild soap and water to remove any dirt or possible irritants.
Apply a soothing treatment, such as aloe vera gel, witch hazel, or a fragrance-free lotion to calm the skin.
Use an over-the-counter hydrocortisone cream or oral antihistamine if the itching or redness is significant.
Avoid scratching, since it can lead to further irritation or infection.
If the irritation worsens, shows signs of infection (swelling, pus, or spreading redness), or doesn’t clear up after a few days, consult a healthcare professional—it may be a reaction to another type of insect bite.
Check for the real culprit
Since fungus gnats can’t bite, look for other insects that might be responsible, such as biting midges (no-see-ums), mosquitoes, or fleas. These pests often appear in similar environments and can cause itchy welts or bumps that people mistake for “gnat bites.”
Eliminate the fungus gnat problem
Even though they’re harmless to people, fungus gnats are a nuisance and can harm plants. To get rid of them:
Let soil dry out between waterings—gnat larvae thrive in damp, organic soil.
Remove decaying plant material and clean up spills or buildup of organic debris.
Use yellow sticky traps near plants to catch adult gnats.
Treat soil with BTI (Bacillus thuringiensis israelensis) or beneficial nematodes to kill larvae safely.
Improve air circulation and drainage to prevent future infestations.
Fungus gnats won’t bite you—but their presence signals excess moisture and decaying organic matter nearby. Managing those conditions will eliminate the gnats and reduce the chance of confusing them with other biting pests.