Do Gnats Bite: Reasons and Treatment Tips

Find out what is a gnat bite, how they get into your home, the types of gnats that bite people and animals, and prevention tips to keep them away from you forever.
Phyllis McMahon
Phyllis McMahon
Research Writer
Phyllis teaches English Literature at a local college and loves writing in her free time. She’s also a great cook – her British beef Wellington is something the best res read more
Reviewed By
Chas Kempf
Chas Kempf
Expert Consultant
Chas works in a professional pest control company and knows all the nuances of this job. Also, he’s a fantastic tennis player and loves to organize BBQ parties for his fam read more
Last updated: August 26, 2023
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Understanding how different pests and insects act can be challenging. Many of them have unique characteristics and a myriad of different species. That’s why when you ask do gnats bite, the answer isn’t always a simple yes or no. You see, gnats have the ability to bite but may not be able to really bite a human in a way that will impact them. This will heavily depend on the species of gnat more than anything else.

In this guide, we will dig a little deeper into this topic and learn more about the question do gnats bite or sting? There are a lot of interesting details to be familiar with, so you can protect your home when needed. Plus, gnats are just plain pesky!

What Are Gnats?

Are you familiar with what a gnat ultimately is? If you want to know whether or not gnats bite humans, you need first to understand this insect a little bit more. A gnat Trusted Source What are Gnats? Are Gnats Flies? Ask an Entomologist Gnats is a colloquial term for “small fly”. They belong to a suborder of flies called Nematocera, which are characterized by their small antennae. is basically just a tiny little fly. They have nearly all the same characteristics of a fly, but they are much smaller insects. These tiny insects have black or brown bodies and then thin wings that are attached to their backs. They also have long legs to land on surfaces.

There are more than 1,000 different gnat species Trusted Source 12 Different Types of Gnats Gnats feed and breed near moist soil, and that is why they often enter your home uninvited looking for food. Whether it be gall gnats, buffalo gnats, phorid flies, or any of the 12 types of gnats, they are each unique in appearance and behavior. . However, if you see gnats in or around your home, they likely fall into the species of fruit flies, fungus gnats, or drain flies in most cases. Black gnats is an umbrella category that contains the 1,000 species mentioned above.

If you’re dealing with a gnat problem that you just want to get rid of, consider one of these best fly repellents to help out. Users say these options really work for reducing pests.

Fungus Gnats

Do Gnats Bite: Reasons and Treatment Tips
Fungus gnats are small flies that infest soil, potting mix, other container media, and other sources of organic decomposition.

Fungus gnats Trusted Source Fungus gnats Fungus gnats infest soil and container media, where larvae feed on organic matter and roots, feeder roots and root hairs. are a species of gnat that prefer fungus. Fungus gnats bite mostly things like fungi, roots, mold, grass clippings, and organic materials. They much prefer plants or flowers that have some sort of fungus life growing near them. These pesky insects typically complete their entire life cycle within only 30 days, but they do reproduce heavily. The good news is that while they might bite if they feel threatened, it’s really unlikely. Fungus gnats also cover plant gnats, lawn gnats, and other similar species.

Plant gnats bite very rarely when it comes to humans, as do lawn gnats. Really, these types of gnats are all alike in that regard. If fungus gnats do bite humans, they are not dangerous to them in doing so. They do not transmit disease. They can harm your plants over time, though.

Drain Flies

Do Gnats Bite: Reasons and Treatment Tips
Stagnant pools of water, particularly in pipes and other drainage areas, attract drain flies. These small, gnat-like insects feed on and breed in sewage.

Do drain gnats bite? Well, much like the fungus gnat, these small, annoying gnats are not likely to bite you. Very rarely do drain gnats bite humans. This species also has a very short life cycle that is less than 40 days long. They like moist areas and will be attracted to things like drains in the home or even storm drains. It’s possible also to find them around gutter areas too. These nasty buggers often hang out in swarms but remember, drain fly gnat swarms don’t bite people or animals in most cases.

Once you get an invasion of these, it can be hard to get rid of them. The first step is to eliminate moisture, but you might also need the added help of repellents or even traps. These insect traps work well if it’s a low-lying drain that’s causing a gnat problem.

Biting Midges

Do Gnats Bite: Reasons and Treatment Tips
Biting midges are minute to tiny flies that can be severely biting pests of humans, pets, livestock, and wildlife.

When you’re looking for what gnats bite or sting, biting midges Trusted Source Biting midges Information on biting midges and how to prevent being bitten. is certainly one to be aware of. They hit all the points. They could bite humans, or these gnats bite dogs as well. These gnats have been known to bite cats and other small animals at times too, but humans and dogs seem more likely to experience a bite. Gnats bite in clusters when they do bite, so that will be a sign to watch for if you’re concerned about bites.

These biting flies are some of the most vicious ones out there, particularly for your dogs. If you know you have them around, you might want to protect your dog with one of these best mosquito repellents for dogs. In most cases, biting midges are most active during the early morning hours or the evening and dusk hours.

Biting midges do fly in swarms typically, and the gnat swarms will bite, which may lead to a higher number of bites.

Black Flies

Do Gnats Bite: Reasons and Treatment Tips
Those flies may appear when a small animal such as a mouse, rat, squirrel, or bird dies within a wall, ceiling, or floor void.

Black flies, or black gnats, bite as well. You might also hear them referred to as buffalo gnats or turkey flies. Only some black gnats bite humans, and it’s the females. Male black flies prefer to only feed on nectar, which means they won’t bite or sting you unless they feel trapped or threatened. However, females feed on blood, and their bites can really do a number on a person. These gnats leave bite marks, but they won’t be as prominent as a biting midge.

The symptoms are more severe, but the bite is less noticeable, aside from bleeding. You’re likely to experience things like itching, burning, blood spots, and possibly even a fever. The bad thing about these is those symptoms could last for a few days when bitten. People are common victims, but your livestock and outdoor animals might also fall prey to the blood-sucking females.

While their bites are certainly unwanted and can hurt, they likely won’t be carrying disease in most countries. They can potentially carry diseases in Africa.


Do Gnats Bite: Reasons and Treatment Tips
Sand flies transmit diseases to animals and humans, including a parasitic disease called leishmaniasis.

The third type of gnat that is known to bite is the sand fly. Unfortunately, sand flies Trusted Source A sand fly Sand flies are characterized by their densely hairy wings, giving them a moth-like appearance. are also known to carry diseases at times, so these are a pest you definitely want to watch out for and take proactive action against if you see them. These flies are very small with a golden, brown color to them. They have long legs and humped backs. When they are in a resting position, their wings are in a V-shape. Now, even though these gnats bite humans and animals, it’s only the females that do so. Male sand flies are unable to bite or suck blood.

However, the females can bite and suck blood and will willingly do so. They don’t like the wind and don’t fly strong, so windy conditions tend to repel them. They are not as likely to bite as some of these other types of gnats mentioned, but their bite could be the most dangerous. This is because they can carry sandfly fever, as well as some other transmittable diseases. The risks of these issues are minimal within the United States.

Fruit Flies

Do Gnats Bite: Reasons and Treatment Tips
Research shows that fruit flies can transfer germs from a dirty surface onto a clean one. Some of the bacteria they may carry include salmonella, E. coli, and listeria.

Fruit flies are much like the drain and fungus gnats we covered earlier. While these flies are annoying, the likelihood of these gnats and fruit flies biting humans is slim. They much prefer juicy fruits and sweet items. They love fruits, vegetables, honeydew, and anything that is decaying as well. Most of the time, when you find them in your home, it’s because they came in with the fruit. If you find them outside, you likely have something sweet that appeals to them.

These gnats only live about 30-60 days, but they reproduce as many as 500 eggs in a cycle, which means they are hard to get rid of once they start!

Can Gnats Bite Humans?

You might be interested to know that the majority of gnats you find around your home are unlikely to bite humans. That being said, it’s not impossible. Around your home, particularly around pets, you are most likely to find biting midges. It is also possible to see sand flies or black flies, but they are less common. While house gnats bite very rarely, it’s possible. The reason they don’t really bite is that they simply don’t have mouths that accommodate biting through the skin.

Can Gnats Bite Pets?

Just like with the gnats that bite humans, there are some species that can bite your pets. The gnat that is most likely to be a nuisance to pets like cats or dogs is biting midges. These gnats bite cats, dogs, and humans. They tend to leave behind uncomfortable, itchy welts on all of these creatures. You can treat your pets to help repel them and protect their skin from the annoying bites. You can do things to protect yourself as well.

Why Do Gnats Bite?

You will find that common gnats like the fruit gnats, drain gnats, and fungus gnats don’t bite. They might attempt biting if they feel threatened, but generally, it won’t penetrate the skin. The other gnats, such as sand flies, biting midges, and black gnats, bite because they feed on blood, so you are a meal source for them, quite a bit like mosquitoes. In some of these species, only the female is capable of really biting, though, so you have a 50/50 chance.

Gnats Bite Symptoms

Do Gnats Bite: Reasons and Treatment Tips
The bites usually cause tiny, red bumps that are itchy and irritating. Sometimes there might be an allergic reaction.

Here are the most common symptoms associated with gnat bites. Notice that these symptoms are similar to some mosquito bites.

  • Itching
  • Red welts or swelling on the skin
  • Fever (in some cases)
  • Pain or discomfort
  • Bumps and clusters of bites
  • Blood spots on the skin

Gnats Bite Treatment

If you experience a gnat bite, there are some treatment solutions you can try to help relieve any pain or discomfort. Here are some great options.

Pain-relief Ointment

Do Gnats Bite: Reasons and Treatment Tips
Topical anti-inflammatory creams can reduce swelling and pain caused by many health conditions and injuries.

Since gnat bites can leave behind pain and discomfort, a pain relief ointment is a great option to help reduce the symptom! Rub it onto the bites and enjoy some much-needed relief.

Anti-itch Cream with Hydrocortisone

Probably the worse symptom of these bites is the itching. But you don’t have to suffer and itch. Grab some anti-itch cream and soothe the itch easily. It’s best to use a cream with hydrocortisone for this, as it will be the most effective at relieving the itch for you.

Calamine Lotion

Many people think of calamine lotion as treating poison ivy, but why not treat the itch and discomfort of bites? It will help dry up the bite, relieve the itch, and improve the symptoms quite quickly. The only downside is that some calamine lotion is pink on your skin.

Cold Compress

Do Gnats Bite: Reasons and Treatment Tips
Cold numbs the affected area, which can reduce pain and tenderness. Cold can also reduce swelling and inflammation.

A cold compress, such as an ice pack or even a cool cloth, can be a great way to alleviate some of the discomforts of a gnat bite on your skin. The cold compress will soothe itching and burning and will also help with any swelling you might be experiencing.

Apple Cider Vinegar

Apple cider vinegar offers a lot of natural solutions, and relieving bites like these are just one of them. Some people drink apple cider vinegar, but for this purpose, you don’t need to do so. Try dabbing some on a cotton ball and then applying it to the bite. It will relieve your symptoms and help the bites to start healing faster.

Baking Soda Paste

Do Gnats Bite: Reasons and Treatment Tips
Make a paste of baking soda and water and apply it to the affected area to relieve itching. Apply a cold, used tea bag to the affected area to reduce swelling and redness.

Another great home remedy, if you don’t have creams and other things on hand, is baking soda. Create a paste that is two-part baking soda and one part water. You don’t need much. Apply this paste to your bites. It acts like a drawing salve and draws out the ailments of the bite to help alleviate your symptoms.

How to Prevent Gnat Bite

Understanding how to treat your gnat bites is certainly helpful, but what if you can be proactive and prevent them, to begin with? Not all gnats bite, but the ones that don’t are still a nuisance. In those cases, you could try something like these best fruit fly traps to repel them away.

Use a Bug Repellent Spray

Do Gnats Bite: Reasons and Treatment Tips
When going out, especially in the forest, it’s necessary to use a repellent. Choose those with natural ingredients.

A bug-repellent spray for you and your pets is a great option to prevent bites. You can use bug sprays that you spray on the person, but you might also want to consider something like this natural spray repellent that you can use on your surroundings too.

Wear Long, Protective Clothes

You can also protect yourself with clothing. When you’re going to be outdoors, particularly in areas that are more susceptible to gnats and insects like these, you can wear long sleeves and pants to cover your skin. Covering your skin will definitely give them less space to try to bite you.

Attach Bug Screens Around Your Home

Do Gnats Bite: Reasons and Treatment Tips
They keep out smaller flying bugs and gnats. It still allows ventilation and visibility. Plus, because it is tightly woven, it provides some daytime privacy.

If you have a patio, deck, or porch that you like to hang out on, attaching bug screens is a great idea. This will allow you to sit outside and enjoy the fresh air but also act as a barrier to keep those pesky gnats and flies out.


1. Can gnats transmit disease? 

Some gnats can carry disease, but in most locations, it is very rare for them to do so. In the United States, it is nearly unheard of.

2. How long do gnat bites last? 

It depends on the bite, but most bites will last anywhere from a few days to a week.

3. Are gnat bites more painful than mosquito bites? 

Some gnat bites are more painful, but the majority of them are similar or comparable to mosquitoes.

4. Is it possible to prevent gnat infestation? 

Yes, it is possible, but sometimes gnats come in without you realizing it. Be proactive with repellents and take action if you notice them.

Final Thoughts

Gnats are pesky little creatures, but the majority of them are harmless. Once they find a way in, they can be hard to get rid of. It’s important to know how to repel them or prevent them completely. The answer to the question “do gnats bite” is really it depends. In some cases, gnats do bite. Those bites can be painful and uncomfortable for several days. However, the gnats that do bite are fairly limited, and the species that bite, only the females, usually bite. It’s still important to protect yourself from bites if at all possible and be aware of the possibility.


What are Gnats? Are Gnats Flies? Ask an Entomologist
12 Different Types of Gnats
Biting midges
A sand fly
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