What bit me in my sleep?


Have you ever woken up with a welt on your leg, a line of red bumps across your belly, or itchy ankles? Has your child ever stumbled down the hallway in the morning, seen with a huge yawn, backwards pajamas, the wildest of stuck-up hair (not atypical) and red dots on their cheek (very atypical)? Who wants to wake up with the horrifying realization that some-biting-thing has been in your bed at night? Who wants to start the day wondering what bit me or feasted on my child during the nighttime? Not me.

There are a few bugs that may visit you (and bite you) at night while you peacefully sleep. They’re quiet while you snore, most promise not to immediately wake you, and their probable not-so-friendly evidence often comes as a very unwelcome surprise as you awake in the morning. You may not even be able to see (or find) these culprits.

These, folks, tend to be one of the following five bugs: bed bugs, fleas, chiggers, mosquitoes, or spiders. I’m going to identify what they look like, what their bites look like, and what evidence they leave behind.

Bed bugs



Adult bed bugs are tiny—the size of an apple seed or smaller. They’re long, brown, and have a flat, oval-shaped body. That is, of course, if they’re hungry and looking to feast on your blood. If they’ve already found and fed on you, though, their body is balloon-like, reddish-brown, and more elongated.


Bed bug bites occur in clusters and are concentrated around areas of exposed skin. They typically nibble around your armpits or your neck, behind your knee, or on your inner thigh. Their pattern of biting may appear as a line or a zigzag, in accordance with the edge of a sheet or mattress.

Bed bugs are smart. They pierce your skin with an elongated beak, through which they withdraw blood, when you’re in a deep rhythm of sleep and are experiencing a temporary paralysis of the muscles. This is just an hour or two before sunrise and only lasts a few minutes.

You probably won’t awake when a bed bug is snacking on you. In fact, you may remain completely unaware of their midnight attack until the bites "appear" later in the day, when they become red, itchy welts. It may even be days until the symptoms appear.


A sure way to identify if you or your children have been bitten by bed bugs is the evidence of the dark, rusty-colored stains that they just left behind on your clean, crisp beige-colored sheets, your son’s dinosaur-themed bed sheets, or your white mattresses. These dark stains are their fecal spots, which are basically dried up, digested blood.




These pests are very tiny—the size of the tip of a ballpoint pen. These flat-bodied, wingless parasites have brown or brownish-red bodies and are covered in hair, allowing them to root to their host and easily move under their host’s fur or hair.


Flea bites look like small red spots, which may have a distinctive red "halo" around the very center of the bite, and often come in clusters or lines of three or four. Fleas tend to bite around the ankles and legs, but may also feast in your armpits, around your waist, and in the bends of your knees and elbows.

The following indicators can help you differentiate between a flea bite and a bed bug bite, as you’re painstakingly aware that you’re getting bit at night, but aren’t sure if it’s a flea bite or a bed bug bite.

Flea bites:

  • Cause small dark red bumps on your skin
  • May appear grouped together in threes or fours
  • Are usually on the lower half of the body, or in warm, moist areas like the bends of elbows or knees

Bed bug bites:

  • Cause a dark red spot in the middle, with raised skin
  • May appear in a cluster or a row
  • Are usually on the upper half of the body, around the face, neck, and arms

To prepare for their first bite, fleas use their strong claws on the ends of their legs to attach themselves to their host. They then piece your skin with their mouthparts, which includes a tiny needle (proboscis), and begin to suck your blood. Flea bites are often itchy and irritating, as most people’s bodies react to the flea saliva (that they secrete into your bloodstream) like an allergen.

Fleas look for easy targets, meaning that they might munch on you while you sleep, especially if you have a pet that sleeps with you. (Though, their personal preference is animal blood.)

These bugs leave behind extremely itchy, red, and sometimes sore welts. Symptoms of their midnight feasting may begin within hours of being bit.


Fleas, like bed bugs, leave behind a trail of tiny black speaks of excrement. Unlike bed bugs, though, fleas will live in any part of the house. So, if you’re finding this fecal proof in areas of your home aside from your bedroom, you have a flea (not a bed bug) infestation.




Chiggers, also called red bugs, are minuscule in size (around 1/50th of an inch) and typically need a magnifying glass to be spotted. When they cluster, though, and because of their red color, you just might be able to see them. (After they feast, they turn a yellowish color.)


Chiggers will bite in random parts all over your body, though they have a particular fondness for legs. Because they can remain attached to the same spot for several days, bites generally appear in groups.

In response to a chigger bite, the skin around the bite hardens, becomes irritated and inflamed, and an itchy red welt develops. These itchy red bumps can look like pimples, blisters, or small hives and will get bigger and itchier over several days. As the skin swells, it may completely envelop the feeding chigger, making it appear as though the chigger has burrowed into the host’s skin.

Chiggers do not eat blood. Using their claws to grab tightly to your skin, they pierce your skin with their razor-sharp mouthparts and then inject their saliva into it, liquefying it so that they can feast greedily upon it. (To be more specific, they dine on the cells of their host’s skin.) They fall off after about four days.


Unlike bed bugs and fleas, chiggers leave behind no noticeable evidence.

It’s important to note that while chiggers can bite you while you’re sleeping in your bed, they’re much more likely to bite you during the spring, summer, or fall while camping or sleeping outdoors.




Mosquitoes are mostly gray in color and have distinctive long legs and a long tube-like mouth (proboscis) that the females use to drink blood (which is a good source of proteins, iron, and amino acids and helps to grow their eggs). Although they appear fragile, mosquitoes are actually extremely resilient insects.


Mosquito bites are isolated and generally appear in a random manner over parts of the body that are not protected by clothing, such as your face, the back of your neck, and your legs. I guess their location depends on what pair of pajamas you wore to bed that night!

Once one of these annoying pests begins feeding, it can carry on for quite some time, resulting in a fair amount of red bites. These bites typically look like puffy, reddish bumps that appear just a few minutes after the bite. The skin surrounding a bite may also be red. A day or so after the bite, these bumps become reddish-brown.

A mosquito’s bite itches, as the mosquito has just injected its saliva (aka spit) into your skin. Your body reacts to this saliva by releasing histamine. This histamine causes the itching and inflammation.

Many types of mosquitoes are more active at dusk and at night, which makes your sweet slumber a perfect time for them to feast.


Mosquitoes leave behind no fecal trace. Their high-pitched buzzing and your persistent itching is proof enough.




All spiders have two body sections and eight jointed legs. Spiders either have six or eight eyes, whose size and arrangement is different, two small "mini-legs," which they use to grab their prey, and fangs. Most have venom glands and the females are often much larger than the males.


Spider bites are typically singular and can be found anywhere on your body. Their bites are often unintentional or in response to a perceived threat, which is why nighttime bites are rare. Spider bites usually leave tiny side-by-side puncture marks on the skin, which can generally be seen with the naked eye.

Spider bites are similar to other bug bites, causing red, inflamed, and sometimes itchy or painful sores. They may go unnoticed and, if harmless, produce no other symptoms.

Many spiders are nocturnal, but the ones that you’d want to worry about don’t often make an appearance in your home, and especially not in your bed. Black widows prefer to hide outdoors and brown recluses will purposefully avoid you.


Spiders spin webs. If you’re seeing a tangle of them in chandeliers, hard-to-reach corners, and along ceiling beams, you, my friend, have visitors. These eight-legged visitors will not leave on their own.


Final word on what bit me in my sleep

We at Dr. Killigan’s greatly value play and sleep. In order to play well, though, you need to sleep well. Sleeping well is only possible if you don’t have any nighttime visitors. Fleas and mosquitoes can quickly become a nuisance of the past with a swift spray of our Six Feet Under. Our Insect Buster, filled with Dust to Dust, a superb alternative to diatomaceous earth, packs a wallop for any spiders or bedbug infestations. Don’t go another night wondering what to do about those visitors in your bed. Rid your bedchamber with our line of non-toxic products that are safe for you, your beautiful children, and your beloved pets.

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