Not all gnats bite. The ones that do — biting midges, black flies and sand gnats — are the females, which need a blood meal to develop their eggs. Males of the same species feed on nectar and cannot bite at all. Fungus gnats and fruit flies, the two kinds most people find indoors, have no biting mouthparts.
A bite from a biting gnat leaves a red welt a few millimetres across, often with a visible puncture at the centre, and it commonly itches for several days — noticeably longer than a mosquito bite. That persistence is the main reason people mistake an ordinary bite for an infection.
Most bites need nothing more than soap, cold water and an antihistamine. See a doctor if the welt spreads outward, weeps, or comes with a fever, since those point to a secondary infection rather than the bite itself. If you are not certain what bit you, the gnat identification chart is the fastest way to narrow it down, and there is more on what you need to know about the traps that catch them.
What Are Gnats and Which Ones Are Biting Gnats?
These insects are tiny flies. Some of them are as small as 1/25″ long. Others range from 1/8″ to 1/4″ long. These insects are weak fliers and can’t fly in straight lines.
There are three main varieties of biting gnats – midges, sandflies, and black flies. These insects have four razor-sharp blades in their mouth that can cut your skin open and leave it itching badly.
Gnats are very much like mosquitoes in that they like warm, wet environments, and these bug bites humans to ingest blood. Female gnats are usually the ones that bite, while male gnats feed on plant nectar.
Biting Midges or No See Ums
Midges, the tiniest of gnats, also have the nastiest bite. When you get an insect bite but you never saw what bit you, that’s probably a bite from a midge. They’re often so small that they can’t be seen by the naked eye.
Sand Flies
These flies are a bit larger than midges, about 1/8″, so you’re more likely to see these buggers before they sink in their teeth. Sand flies fly and feed in swarms, so you’re likely to get bit by these insects while walking through a cloud of them.
Buffalo Gnats or Black Flies
Black flies are the largest of these insects, ranging from 1/5″ to 1/4″. If you’ve ever been hiking during the late spring and early summer, you’ve likely encountered a swarm of black flies.
Why Do Gnats Bite Humans?
It turns out that gnats bite humans for the same reason that mosquitoes do: to get a blood meal. These insects are attracted to the carbon dioxide that we exhale, and when they land on our skin, they pierce the skin with their sharp mouthparts to get to the blood.
What makes these insects even more annoying is that they inject an anti-clotting agent into the wound when they bite. This prevents the blood from clotting and allows the gnat to feed for longer.
Where Are Gnats Found?
These insects can be found pretty much anywhere, inside or out. The key ingredients for their perfect habitat are moisture and warmth. Outside, these bugs love to congregate around standing water and swarm around moist dirt on hot days.
This is why they’re often found in the woods, but gardens and compost piles are also ideal hangouts for these bugs.
They also love houseplants and compost buckets. If you’ve got food scraps in your trash, they may hang out there too.
What Are the Common Symptoms of a Gnat Bite?
When you first get bit by a gnat, you’ll feel a sharp burning sensation at the site of the bite. This is because of the anticoagulant that a biting gnat injects when they bite so they can ingest your blood without it clotting. The area around the bite will turn red and may swell.
For some people, this swelling is mild, but others will experience a lot of swelling at the site of the bite. Some people experience a serious or minor allergic reaction to gnat bites that results in severe swelling and even blisters. The site of the bite will also be very itchy.
Most gnat bite complications are because of infection of the bite site. Unlike mosquito bites, bites from these insects tend to break the skin. These insects use the cutters inside their mouths to cut the skin.
Some people experience more serious reactions. They may develop a fever a few hours after being bitten. People allergic to these insects may break out in hives and have trouble breathing. These more serious symptoms aren’t common, but they happen.
As with any other insect bite, you probably won’t know you’re allergic until you get bitten for the first time. If you notice the following symptoms – serious swelling, a fever, hives, or difficulty breathing, contact your doctor immediately.
Do Gnat Bites Cause Severe Allergic Reaction?
Do you know what causes severe allergic reactions? If you guessed insect bites, you’re right! Gnat bites are a common cause of severe allergic reactions.
In fact, they’re one of the most severe types of bites that can cause anaphylaxis, which is a potentially life-threatening condition. Symptoms of a severe allergic reaction include difficulty breathing, swelling of the throat and tongue, and dizziness or fainting.
Of course, some people experience a mild allergic reaction, which could last for a week.
If you have insect allergies or experience any of these symptoms after being bitten by a gnat, it’s important to seek medical help immediately. Fortunately, severe allergic reactions to these bug bites are rare, but it’s still important to be aware of the potential risks.
Do Gnats Carry Diseases?
Thankfully, these insects do not carry or transmit the same serious diseases that a mosquito bite can carry. Mostly, biting gnats only transmit diseases to livestock.
While black flies don’t transmit disease, their bites can transmit a parasite that causes disease in humans. Gnats who carry the Onchocerca parasite can deposit the parasite’s larvae into the skin of a human when they bite.
If the bite is not treated and the larvae mature in the human body, it can lead to a disease known as onchocerciasis. This is a very serious illness that can lead to a painful skin rash, bumps under the skin, swelling of the lymph nodes, and even blindness.
When you develop any of these worrying symptoms after being bitten by a gnat, seek medical treatment immediately.
How Should You Treat Gnat Bites?
Gnat bites can usually be treated at home with basic first aid measures.
Wash the Site
Use cold water and antibacterial or mild soap to wash the bite site. This helps remove the anti-clotting agent that these bugs inject with their bite, which can help relieve the burning sensation at the bite site.
Washing with warm water and antibacterial soap also helps prevent infection. Since these bugs can land on rotten food, garbage, or dead animals, they can pick up bacteria, so it is good to clean up the site to avoid bacterial infection.
If you have numerous gnat bites, you might want to take a cold shower instead.
Apply Antiseptic
After the bite site has been washed, an antiseptic should be applied. You can use rubbing alcohol, iodine, or hydrogen peroxide depending on your preference.
Once the affected site has been washed and antiseptic has been applied, you can use various remedies to reduce the uncomfortable symptoms.
Apply Apple Cider Vinegar
You can also try a popular natural home remedy – apple cider vinegar. Apple cider vinegar can be applied to the affected area to reduce itchiness and swelling. Soak a cotton ball with apple cider vinegar and apply to the affected skin site.
Apply Anti-Itch Cream or Essential Oils
Consider applying anti-itch cream to the affected area. Anti-itch creams will help to soothe the skin and provide relief from the itching.
Some people swear by essential oils for treating gnat bites. Many of the essential oils that will help ease the pain of a gnat bite also have antiseptic properties, so using essential oils can also help prevent infections.
Try applying peppermint oil, tea tree oil, chamomile oil, or lavender oil to the affected area to help relieve itching.
Apply Cold Compress or Ice Pack
If you find yourself being bitten by a bug, one way to help relieve the symptoms is to apply a cold compress to the affected area. The cold temperature helps to numb the skin, and can also help to reduce swelling.
Just be sure to wrap the compress or ice pack in a clean cloth, and avoid placing it directly on your skin. This is useful for all kinds of bites from flying insects that tend to suck blood.
When you’ve tried these treatments and your symptoms don’t improve after a few days, contact your doctor. Gnat bites can lead to various medical issues if left they don’t heal properly.
What Should You Do to Prevent Gnat Bites?
There are a few ways that you can protect yourself from gnat bites.
If you’re headed outside into gnat-friendly habitats, choose the time of day wisely. These insects love to come out at dusk and dawn, so planning your outdoor activities during other times of the day can help prevent insect bites.
Cover Exposed Arms and Legs
You can also prevent insect bites by choosing your outfit wisely. Most of these bugs aren’t able to bite through clothing. Wear long-sleeved shirts and long pants when you’re headed into gnat territory can ensure they can’t get to your uncovered skin.
If you’re headed out during gnat prime time or to a place where gnats love to swarm – like rivers, lakes, and streams – wear a mesh net over your face to prevent insect bites.
Apply Insect Repellant
Insect repellents are also effective. The insect repellent you use depends on your preferences about which chemicals you expose yourself to.
If you prefer a natural alternative, you can try products with lemon eucalyptus. This essential oil is an effective insect repellent. It works against gnats and other insects.
How Should You Get Rid of Gnats in Your Home?
Once you get gnats in your home, getting rid of them can be tricky.
The best option is to use a sticky trap. When gnats fly into these traps, which are sticky on both sides, the black gnats and other flies get stuck and eventually die. Place sticky traps throughout your home in places that provide the perfect gnat habitat.
Hang them in the pantry, the kitchen, and around the garbage or compost bucket. You can also attach them to the outside of potted plants. Prevention is the best way to deal with gnats. So, once the traps eliminate your infestation, take steps to prevent further gnat problems.
Dealing With Gnats
Gnats are annoying little buggers, but dealing with them doesn’t have to be! The same goes for these bug bites. Follow the simple steps in this guide to prevent gnat bites and infestations.
For more information about dealing with gnat problem and other pesky insects, check out our blog.
Do Gnats Bite at Night, and Can They Bite You in Bed?
Yes, gnats bite at night. Biting gnats are active during the day and after dark, and indoors they tend to stay close to whatever drew them in — houseplants, damp potting soil, a drain, or standing water. If that happens to be in your bedroom, you can absolutely wake up with small red bumps on whatever skin was uncovered.
Only the females bite. Males feed on plant nectar; females need a blood meal to produce eggs, which is the same reason female mosquitoes bite and males do not.
If you are waking up with bites, check what else is in the bed
This is worth getting right, because the wrong answer wastes weeks. Gnats are flying insects that land, bite and leave. They do not live in your mattress and they do not leave droppings on your sheets.
Dark specks on the bedsheet, seams or mattress edge are a sign of bed bugs, not gnats. So is a line or cluster of bites on skin that was covered by bedding. If you are seeing either of those, treat it as a bed bug problem and not a gnat problem — nothing on this page will help you, and a gnat trap will not either.
Gnat bites, by contrast, are scattered, land on exposed skin, and usually come with visible small flies in the room.
What actually reduces them
Indoors, biting and fungus gnats come from a breeding site, and removing it does more than anything else: let houseplant soil dry out between waterings, clear drains, and deal with any standing water. A hanging fly stick placed near the plants or window will catch the adults flying around a room, which brings the numbers down while the source dries out.
Be aware of the limit: sticky traps work on the small flies circling indoors. They do not do much against biting midges and no-see-ums outdoors, which arrive from marshy ground well beyond your yard. Outdoors, long sleeves at dawn and dusk and a repellent do more than any trap.
