Do gnats bite?

Do gnats bite?

I don’t typically think about getting bitten by a gnat. I’m generally more concerned with mosquito or horse fly bites. Well, now gnats are on my list of bugs to stay away from too.

What are gnats?

Gnats are small, thin-winged, black or dark brown tiny flying insects with slender bodies and long legs. The most common types of gnat-like insects that you’re bound to find in your home are fungus gnats, fruit flies, and drain flies (also known as phorid flies). They are often weak fliers and tend to fly in large numbers, called clouds.

If you’re unsure of whether or not you have gnats or fruit flies, there are key differences between the two species. One primary difference is their eyes: While fruit flies have large eyes, the eyes of gnats are difficult to identify with the human eye.

What is the life cycle of a gnat?


A gnat’s lifecycle goes through four life stages: egg, larvae, pupae, and adult. It is short and contingent upon a number of factors, including:

  • Species of gnat-like insect
  • Species reproductive potential 
  • Availability of food sources
  • Access to moisture
  • Protection within their habitat 

The lifespans of the most common types of gnat-like insects is somewhat similar, but isn’t as important as how quickly they can reproduce. It’s their rapid reproductive abilities that’ll keep these pesky intruders flying around your kitchen, your bathroom, or other areas of your home.

Fungus gnats

  • Adult Lifespan: 7-14 days
  • Life Cycle: 8-30 days
  • Egg Production: 100-150 eggs
  • Habitat: Near potted plants, primarily spider plants, african violets, peace lilies, geraniums, and inch plants.
  • Diet: Organic mulch, fungi, root hairs, leaf mold, grass clippings, and compost.

Fruit flies

  • Adult Lifespan: 40-50 days
  • Life Cycle: 35-60 days
  • Egg Production: 500+ eggs
  • Habitat: They are usually found hovering over decaying vegetation or rotting fruit.
  • Diet: Fruits, vegetables, decaying material, and honeydew (secretion) produced by aphids

Drain flies (Phorid Flies)

  • Adult Lifespan: 8-14 days
  • Life Cycle: 8-37 days
  • Egg Production: 30-100 eggs
  • Habitat: House and storm drains, which are moist areas that are coated with nutrient-laden organic material.
  • Diet: Decaying matter and sludge that builds up inside drains, manure, animal carcasses, and decaying fruits and vegetables.

Do gnats bite?


There are biting and non-biting species of gnats. The types that you’re most likely to find in your home (fungus gnats, fruit flies, and phorid flies) are all non-biting. They don’t possess the proper mouthparts to bite and penetrate the skin. 

Some types that do bite are biting midges, sand flies, and black flies. They use the sharp mouthparts to puncture and cut your skin to expose blood which is then sucked into their digestive system. Biting gnats will bite any exposed, uncovered skin. Their bites generally itch, as the gnat produces anticoagulant compounds that allow them to suck blood without the blood coagulating. It is these anticoagulant compounds that you have a reaction to (and want to itch). Stop scratching if you can, as continuous itching can lead to open sores that are susceptible to secondary bacterial infection of the bite wound. 

Biting midges

  • Appearance: Grayish in color, though reddish after taking a blood meal, and 1/25 to ⅛ inch long.
  • Characteristics: Vicious biters (biting any area of the body that is exposed) that prefer to feed during the early morning and evening hours and fly in swarms.
  • Habitat: Salt and freshwater and decaying seaweed that is tossed up on the beach.
  • Symptoms of bite: Pain, plus reddened, itchy, and swollen areas around the bite that begin to show within 30 minutes of being bitten.

Sand flies

  • Appearance: Golden, brownish, or grayish in color, ⅛ inch long, and humped-backed.
  • Characteristics: They are not strong fliers, so you’re not likely to encounter them (or their bites) if it’s windy out.
  • Habitat: Rock crevices, caves, and rodent burrows.
  • Symptoms of Bite: Irritation and skin-related symptoms.

Black flies

  • Appearance: Shiny black in color, ⅕ - ¼ inch long, and with a stout body, legs, and antennae.
  • Characteristics: They feed in swarms, fly around the head, and bite in large numbers.
  • Habitat: They breed in flowing water and the adults seek moist environments, like humid wooded regions.
  • Symptoms of Bite: Itching, burning skin lesions, numerous blood spots where the adult females bite, and sometimes fever. The bites are Initially painless, but bleed a great deal.

What attracts gnats?

Gnats are attracted to moist areas inside your home, such as wet potting soil or wet sinks and drains where food residue can collect. They also gravitate towards decaying organic material, such as rotting vegetation or fruit, food spillage, and open or overflowing garbage cans. Lastly, gnats are also attracted to you - your perspiration, body heat, mucus from your nose, tears from your eyes, and the carbon dioxide you breathe—and your pets.

How do I get rid of gnats?


Gnats can breed and populate in various locations. Following are the best measures to take if you find gnats in areas where they are commonly found—near drains and houseplants.


First, pour ½ cup of salt and ½ cup of baking soda down the drain. Next, pour 1 cup of white vinegar down the drain. Allow the mixture to foam and remain in the drain for at least two hours. In the meantime, do not use the drain. After two hours, rinse the sink and drain with plenty of hot water. Follow this up by spraying Dr. Killigan's SIx Feet Under Non-Toxic Insect Spray into your drain and your sink, which will ensure that no eggs or larvae were missed.


Spray a light mist of Dust to Dust, a superb alternative to diatomaceous earth with proven kill times up to 50% faster, using Dr. Killigan's Insect Buster on your plant.  The Insect Buster's precise distribution capability and targeted application will ensure that you have covered all leaves and stem of this plant. This non-toxic powder is deadly for bugs, but safe for you, your children, and your pets. We do, however, recommend wearing a long-sleeved shirt and taking precautions to not breathe in the dust, as it can cause irritation until settled. 

Where do gnats come from?

Gnats come from the outdoors. I suppose the real question would be ‘Why are Gnats coming into My home?’ Gnats have an amazing sense of smell and find their way into your home because of their attraction to your overflowing garbage, the smell of the sludge in the bottom of your kitchen drain, or the sweet wafts of the overripe bunch of bananas you have sitting on your kitchen table. They may also be in search of water, which could lead them to the drip under your kitchen sink or the abundance of moisture that is found in your potted plants.

How do I prevent gnats from infesting my home?

These are all practical, do-it-yourself tips that are helpful in not only gnat prevention, but overall in-your-home bug prevention. Many insects are attracted to the same types of smells and locations. Ensuring that you can check off every item on this list will greatly aid you in future pest problems.

  • Repair leaks. Make sure to repair leaks around your sinks. 
  • Repair screens. If you find that any of your screens have gaps or holes in them, there is no time like the present to fix them. 
  • Repair cracks or openings. Check windows and doors for any small openings or cracks. Insects are tiny. They need even tinier openings to squeeze through. 
  • Monitor produce. If you keep produce on your countertops, ensure that none of it is too ripe. If you’re unsure, place all produce in your refrigerator. 
  • Keep pet dishes clean. If you feed your pet wet food, be sure to clean up any messes after a feeding and wash the food dishes. 
  • Keep countertops and floors clean. Do not go to bed with any sticky messes around. 
  • Do not overwater your plants. You can test your plant moisture by doing the finger dip test, making sure excess water can drain off, and by using a moisture meter. (Finger dip test: Dip your finger up to your second knuckle; if your finger stays dry and clean, then it’s time to water). 
  • Clean out your sink frequently. Use baking soda. Two reasons: Bug prevention and because kitchen sinks serve as a feeding grounds for illness-causing bacteria, including E. coli, salmonella, and Staphylococcus aureus
  • Scrub the inside of your kitchen drain. Do so with a narrow, long-handled cleaning brush. Removing any organic matter from your dish disposal will leave nothing for the gnats to feed on. 
  • Take trash out. Keep trash bins away from the entry points of your home.

Final word on gnats

If you have any other tips or tricks on gnat prevention, have any true and tested essential oil recipes that you’ve used on gnat bites, or want to share about an experience that you’ve had with gnats, we’d so enjoy hearing from you.

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