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Bug Bites That Cause Swelling

I ran a landscaping business in San Diego, mostly focusing on lawn care.

Bug bites that cause swelling are many and varied.  Read the list to try to identify what kind of bug bite you have.

Bug bites that cause swelling are many and varied. Read the list to try to identify what kind of bug bite you have.

There are many different kinds of bug bites that cause swelling, and no one likes to wake up in the morning to the sight of a bright red lump on their body. The problem with insects and bugs is that they generally are nocturnal. They become active at night when humans are most susceptible to them. But before we talk about which kinds of bug bites that cause swelling, we should discuss a little bit about why bug bites cause swelling.

Depending on the level of sensitivity of the skin, it should generally only swell because a foreign chemical is introduced. This is not necessarily a poison. Some bug bites, such as mosquito bites, inject a chemical solution into the area which keeps the blood they're drawing out from coagulating and clotting so that they can process it. This chemical isn't considered a poison, but it causes swelling nonetheless. Many other kinds of bugs bite even though they aren't poisonous, and these bites shouldn't cause swelling, unless the skin is overly sensitive.

Types of Bites

If you've gotten a bug bite and aren't sure where it came from, this list should help you determine. It goes from most common to least common.

1. Mosquito Bites

  • Like we discussed already, mosquito bites cause swelling due to a chemical they inject into the skin in order to keep the blood from clotting. Mosquito bites aren't dangerous unless the mosquito is infected with malaria, which is a blood borne disease that's very dangerous. But in the United States and other modern countries, malaria is very rare. It generally thrives in jungle climates.

2. Fleas

  • Flea bites are very common in homes, especially homes that have pets. Fleas live happily in carpets and couches and can jump great distances, meaning that they can land on your skin and bite before you even know they're there. Flea bites aren't always able to be felt at the moment of the bite. So if you're noticing small and itchy red bumps but have no idea where they've come from, then you might have a flea problem. Fleas are very small as well, and very difficult to kill. Smashing them between your fingers doesn't usually do the job. So if you capture a flea in your fingers, you may want to wash it down the sink.

3. Spider Bites

  • Spider bites, in general, are very common, but the type of spider can be varied. Common households include Daddy-Long-Legs, which don't bite, and Wolf Spiders. Wolf spiders are usually small to medium size, and aren't among the more poisonous of spiders. Their bites will leave a pink or reddish lump on the skin for a couple of days. The size of the lump generally corresponds to the size of the spider.
  • There are many other kinds of spiders that live nearby homes. These however, are usually more dangerous and leave more than just some simple swelling. These include Black Widows, Brown Recluse, and Funnel Spiders. If you get bit by any of these, you'll know it, and you'll want to seek immediate medical attention. An ordinary household spider bite shouldn't get worse than a small lump. So if yours does, seek medical attention.

4. Bed Bug Bites

  • Bed bugs are tiny parasites that live in beds. There are different varieties of bugs that could be labeled bed bugs, but the one generally thought of is the one that feeds on human blood. Bed bug bites are very similar to mosquito bites in that the swelling comes from the anti-coagulant chemicals that's injected into the region to keep the blood from clotting. Bed bugs are much less common in urban environments than they once were. They've largely been eradicated in the modern world. Bed bugs are able to feed on their host's blood without waking the host.

5. Ants

6. Bees, Wasps, and Hornets

7. Centipede Bites

  • Centipede bites are often very painful. The centipede leaves a pair of puncture wounds through two pointed attack claws that inject a non-fatal poison into its victim. Centipedes are generally encountered outdoors, and can attack a victim when a portion of the body is stepped on. If the victim is wearing sandals and steps on a small portion of the body of a large centipede, the rest of the body can swing upward and sting the foot of the victim. A centipede sting will definitely leave swelling, but you'll feel it right away. Centipedes inhabit mostly the southwestern states.

8. Scorpions

  • Most everything about scorpions is similar to centipedes. The method of attack, the type of poison, and the region are all very similar.

Causes of Swelling

The important thing to realize about bugs and insects is that they don't eat the same way that humans do. Many other living creatures metabolize and eat in very different ways, and often use poisons and other chemicals in order to both catch and eat their prey. These chemicals are sometimes very hazardous to humans and sometimes fairly inert. Some spider bites, for example, such as the brown recluse spider, injects a chemical into the skin that actually begins to break down and digest the skin all around the bite. It's a very nasty type of bite that often causes widespread damage to the area around the bite.

Most bug bites that cause swelling, however, are localized and cause swelling more because of the body's attempt to isolate and deal with the foreign chemical without letting it spread. Most bug bites that swell are fairly safe, and unless the bite persists and gets worse, they should fade away and stop itching within 2-3 days. The body absorbs the foreign toxin and then gets rid of it. But like we said earlier, the most important thing a person can do with a bug bite is to watch it, and if it continues to worsen, to seek medical attention.

This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.


anon on June 20, 2019:

I hate bugs

Anon on June 08, 2018:

I got stung by what looks like a hornet, which I didn't have any serious reactions to it, until a couple days later, I had a hard fall. Now, whenever I wake up, I would have swelling, first my top lip was swollen, then the next day my ankle was swollen, then my hand and fingers, and now My right eyelid, my top lip, and hands and fingers. If anyone can help identify the problem that caused me to swell, please do.

JP on May 07, 2018:

My arm has a huge itchy swollen bite on it. It didn't itch at first and I noticed when I was changing clothes. It seems to be getting bigger. There are two rough red spots in the middle of it.

Anonymous on November 03, 2017:

woke up with a tiny blister in the middle of a slightly swollen and red circle. it's painful, tender, and just a tad bit itchy too. what do you think it is?

Tammy Sawatzky on August 30, 2017:

Hi I was bite by something behind my ear and it is swollen and hurts to touch can not see it and you can't really see what kind of marks it made but my one side of my neck hurts and not sure what to do

Bleh on August 27, 2017:

Hi, I was sitting on my carpet the other day when I suddenly felt a sting on my thigh, the kind that you normally feel when an ant bites. I didn't think much of it and absent-mindedly went on to scratch the affected area. 30 minutes later, that area was a huge swollen bump and my pores were so enlarged I got so worried. What kind of bug do you think it could be? The swelling has now increased in area and it is rather red. Please help!

Anon on August 20, 2017:

I was bitten by some sort of bug or spider on my foot, and the entire foot swelled and turned red. What does this sound like?

Anon on August 19, 2017:

I woke up one day to an extreme itchness on my back part of my foot. It's a very tiny bump and it is white, however the area around it is red. Should I say something?

Rishav Singh on August 11, 2017:

Someone bit me at night but I did not see. Please tell me how to resolve it. My hand is swollen but I cannot visit the doctor.

Amy on August 02, 2017:

I got bitten during the day and opened the wound through scratching (before i realised it was a bite) it was the size of a 20p coin. then this morning it swelled to 2inch diameter and 1cm thick, there is a mark in the middle. it is very hot and feels hard, i have use cream and antihistamines which have helped a little bit with the swelling. Should i just leave it for another day?

Delilah on August 01, 2017:

i was bitten by mosquito and it swelled within 2days it began to swell and release pus

Nathaniel on July 27, 2017:

i got bit by something today and it looks kinda brown and the around of the area is red what do you think it is ?

ally on July 18, 2017:

I was out on the lake yesterday and I got bit a couple times on my ankles I think it was a black fly my ankles are swollen and it hurts to walk on them. there very tense and cant touch them without pain. is this normal or should I be going to emergency

. they are still swollen and this was yesterday

byron on July 02, 2017:

I have no bite mark went to bed and woke up with a left side of my face swollen very badly affected

Liesha on June 27, 2017:

I was out at a cabin, during the night i was bitten by something on my chest. The bite is red, a hard knot. At first it was painful and i could not touch it now it itches. Its going on four days it is still there, still is a big knot. I pushed on it today and blood came out.

Manu on June 21, 2017:

I am bitten by something after 4hrs it swallowed a little solutions

Savannah on June 21, 2017:

I have a bite that's the size of a dollar coin and it's all bumpy and looks like a spider or misquote.

Celina blakeney on June 08, 2017:

My granddaughter was bit by something. It left 2 puncture holes that puss is coming out of and her whole foot is swollen and hot. Very worried. She is at hospital now

Michael Adams on May 13, 2017:

I woke up today with a bite with one hole in it and red swollen area all around it in about an inch in diameter. Can someone tell me what this is? It is also very itchy.

Deb on May 06, 2017:

My index finger was sore yesterday and today at base between my index and pointer fingers it is swollen and causes pain when I bend my hand. Is it a spider bite

Bob on February 28, 2017:

I have a bug bite but I donʻt know what what bite me. It made my lip puffy.

nana on January 23, 2017:

i go to sleep and wake up with bumps with blood in the middle of them, they don't hurt but idk what are they

Ellen on January 16, 2017:

I use the Bug Bite Thing to get rid of the itching and swelling of bug bites. It is a suction tool that extracts the poison from below the skin. Super easy to use and works instantly.

shirlene on December 31, 2016:

a few weeks ago my 22 year old son woke up the next morning complaining that his big toe was itching and very red also it head red circle on top of the toe and in the middle it was a white blister. we put medicine on it,but the next morning it was worse and swollen but it had 3 more white blister on the toe/he went to the dr, the dr said he didn't really know what it was so he gave him an antibiotic for him to take for 5 days, the third day of the medicine he got really sick and complaing of chest pains so he went to the er room,the er dr found inflmation in his lungs and bronchitis plus et was some kind of a bite on his toe maybe a spider bite. yesterday I took him to see his dr cause his toe was very red and swollen and bunch of white blisters on the toe . the dr said he don't think it was a spider bite cause the bites was small like a flea bite,and he didn't want to give him any antibiotic but for him to take a hot bath and soak it and if it don't get better in a week that he is going to cut open the blister to drain it. this morning its worse and red and swollen with more blisters on it. please can someone please tell me what I should do or how to tell the deffernce between a spider bite and a flea bite and if it is a flea bite what can I put on the bite and best home remides can I use to kill the fleas in my house and on dog and cat. please im cocern about him instead of getting better he is getting worse and sicker u can contact me at 970- 697-0704 that's my cell number. sincerely a very concern mom ( shirlene )

elina on December 29, 2016:

I was in Adelaide yesterday and I got a wasp-like feeling on my right hand, I put it in cold water then I applied a cotton swab with vinegar, then I woke up this morning and it's really swollen, where I normally have thin hands I couldn't even see my knuckle, I didn't see what it is but its sore and stiff , helpppppp

_CHELLE_ on November 12, 2016:

Hi, I got bit by something a few days ago, it left 2 red itchy, stinging blisters on my forehead. I was asleep and not aware as to what had bitten me. But I have weird headaches that last maybe 2 minutes if not that and my right eye stings. Can someone please tell me what kind of bites these are? I'm worried because they are getting worse not in size but pain wise.

I on November 05, 2016:

I have about 50 bites between both legs they are really swallen and now my feet and legs are really swallen. They itch and are hot on my skin. Not getting better.

Cristi on September 09, 2016:

I have a huge bite on my leg that is slightly changing colors in some spots. It itches and has swollen to approximately 6" around. There isn't any puncture holes and around the outside of the red is a white ring. What kind of bite am I suffering from?

Ruth on August 18, 2016:

I started inching Tuesday night I rubed some alcohol on it Wednesday it got worse and the area was sore and painful the swelling felt larger so I look in the mirror on my arm near my elbow and on my side beneath my breast was a swelling the size of the Palm of my hand what could've bit me?

Anonymous on July 05, 2016:

Christine, I had that before. Could possibly be a ring worm. Really common in Urban Areas, but they make a ring. If its actually true, you need to not itch it and burn it off, take a napkin, wet it with hot hot water and keep it on it. It will burn off itll be good

Christine on June 14, 2016:

My nine year old is swollen at the base of his head. It's a ring all the way around. Kinda looks like an inner tube

elle on December 23, 2014:

I live in Chinatown, NYC and woke up with a small bite with black in the center, which is sort of ulcerating and red encircling it, though not with a dramatic target shaped ring, just red surrounding it. The black part is like the size of an adult bed bug and then there is an area about the size of a nickel which is slightly pink , swollen and firm. There was, some pus surrounding the black part, too, but it has dissipated. My internet searches only lead me to spider bites, but I can't imagine that I'd have a biting spider in NYC winter. Any ideas?

desmond wooten on August 24, 2014:

Around 4 I felt something crawling when I laid my right arm on the bed I felt a Sharp bite like a bee sting unfortunately I didn't see what bit me I live in Georgia and I think it was a brown recluse spider bite the bite was instant

Johne604 on August 05, 2014:

I loved your blog article. Really Cool. kdbcdgakdfkk

Heriberto Lopez on July 20, 2014:

My girlfriend got bit by a bug. We don't know what kind it is but it looks like a mosquito bite but around the bite it's all red and warm.l it tends to grow a bit bigger with passing day.

Benji Mester (author) from San Diego, California on July 16, 2013:

If you didn't feel it when it happened, that probably rules out anything nasty like centipedes, large spiders, fire ants and the like. Could have been some kind of aquatic bug. It's hard to say what bit you because bodies are different. A bug might bite one person with little reaction, but another person could swell way up. Taking an antihistamine might help since it sounds like your body is overreacting to whatever toxin was injected into your skin.

Ana on July 16, 2013:

well i was in delta utah staying in a friends house on the lake and something bit my big toe, I didn't feel it when it happened but later that night it kind of itched but two days later my whole toe swelled up and it is extremely itchy to the point that it is painful and woke me up in the middle of the night. its red and kind of white, do you have any idea what could have bitten me?

Benji Mester (author) from San Diego, California on July 06, 2013:

Me too. Anything that attacks you while you sleep is pretty horrible. Thanks for stopping by!

Carl Junior on July 06, 2013:

The bites that I fear most are from bed bugs. Those little creators can make you be afraid of going to bed like literally. Great post voted up and useful.

Benji Mester (author) from San Diego, California on June 27, 2013:

Yeah, spiders can be really nasty sometimes. Around where I live, we have the brown recluse which can destroy whole areas of skin. And we have the black widow, which locks down your central nervous system and causes intense pain. Yay :( Thanks for stopping by!

Amy Goldstein from Chesterfield on June 27, 2013:

I once had a friend that got bitten from a brown spider and the bite area bruised. He had to go to the hospital and have them remove the puss from the infected area.

Benji Mester (author) from San Diego, California on June 25, 2013:

Walter, haha, that's incredible. I love it.

Lens, thanks very much!

LensMan999 from Trans-Neptunian region on June 25, 2013:

Very nice hub and the matter is described quite well. Thanks for sharing these useful information.

Poon Poi Ming from Malaysia on June 24, 2013:

Benjimester, you are amazing! Anyway, I've good tidings for you. The zzzing can easily be solved with ABBA's "Thank you for the music":

Benji Mester (author) from San Diego, California on June 24, 2013:

I used to get back reactions to them as well. I think the body sometimes just gets used to the toxin after awhile. I hate that high pitched zzzing you hear when they're close. That's the worst.

Elizabeth Parker from Las Vegas, NV on June 24, 2013:

Oh how I hate mosquitos! I have such bad reactions to their bites, while I know for others, they aren't bothered at all. Great info in your hubs. Voted up!

Benji Mester (author) from San Diego, California on June 24, 2013:

That sounds uniquely miserable. I hate deer flies more than just about any other type of insect. Sorry you have to go through that.

moonlake from America on June 24, 2013:

We have deer flies, horse flies and sandflies and belive me they cause swelling. My hand is about touble it size today because of deer fly bite. Sandsflies get in the hair and it not only causes swelling but it causes pus. Black flies will also do the same thing. Sometimes the black flies are so bad they have to close camping grounds. Our ticks are so bad this year and their bite seems to be different. It swells and stays itchy and red for weeks. Voted up on your hub.

Benji Mester (author) from San Diego, California on June 24, 2013:

Hey there. Thanks for your comment and well wishes. If you're allergic to bees and wasps, you may want to look into buying some locally grown honey. I know it works for other allergens like pollens but I don't know if it would work for the poison found in bee stings. Locally grown honey introduces the body gently to the allergens that usually drive it crazy.

Patricia Scott from North Central Florida on June 24, 2013:

What a timely article...we have had an abundance of rain this summer so far and it has been a blessing but with the rain comes the mosquito. Try as I may I cannot keep ahead of them by emptying every little pot that collects water.

And the horseflies are out this year, too. And of course, red ants think I am a buffet. Wasps? O, yes. I chased two out of my craft room yesterday. All of these cause me some degree of panic as I am deathly allergic to the wasps and bees and ants are almost as bad. However I still face off with them!!! Interesting and well written. Thanks for sharing. Angels are on the way to you and yours this evening. ps

Benji Mester (author) from San Diego, California on June 24, 2013:

A bug bite can cause bumps that look like pimples, but they're not strictly the same thing.

ud1093 from ? on June 24, 2013:

does a bug bite cause pimples

Benji Mester (author) from San Diego, California on June 24, 2013:

Haha, yeah that would be my main worry also.

Poon Poi Ming from Malaysia on June 23, 2013:

Benjimester, Sai Baba was said to be stung by a scorpion and he suddenly had miraculous spiritual powers. I don't mind being stung by a scorpion, if I can manage to achieve what he had achieved... my only worry is that the scorpion story is just that, a story, LOL.

Benji Mester (author) from San Diego, California on June 23, 2013:

Scorpions are supposed to be the worst. I've never gotten stung by one thankfully, but I've seen plenty of them. You're probably right about them being attracted to warmth. Thanks very much for stopping by!

Mel Carriere from Snowbound and down in Northern Colorado on June 23, 2013:

My Dad once got bitten (or stung, really) by a scorpion that crawled inside his sleeping bag at night. I think scorpions are attracted to warmth. In Arizona, where this incident occurred, this is pretty common. The sting was excruciating, but he never went to the doctor.

Benji Mester (author) from San Diego, California on June 18, 2013:

You're right. I hadn't thought about those. I used to get bit by those a lot while down by the water. I'll have to do some research and see what I can add to the article about them. Thanks very much for the tip!

Moronke Oluwatoyin on June 18, 2013:

The sandfly is also a terrible insect. They are so tiny and cause swolleness on all the parts of the body. It took me a year to clear the black spots left on my skin by these insects.


Benji Mester (author) from San Diego, California on June 18, 2013:

For sure. I lived in Southeast Asia for a year, in Cambodia, and I had some friends get dengue fever. It's pretty rough.

idigwebsites from United States on June 18, 2013:

That's why I wear pyjamas right now... especially in this rainy season. I can't tell which mosquito is carrying malaria or not. So I'd be better be safe than sorry. Malaria is deadly, as well as dengue -- that last one is one real killer.

David Walli from Northern Minnesota on June 13, 2013:

Wood ticks and mosquitoes are bad now.

Benji Mester (author) from San Diego, California on June 13, 2013:

Right on. You definitely get some serious bugs up there, so I'm sure you guys have some great tips. Thanks!

David Walli from Northern Minnesota on June 13, 2013:

I read somewhere if you crush several aspirin and make a paste, it could help. Also rubbing a bar of soap over the bite..

Benji Mester (author) from San Diego, California on June 13, 2013:

Sorry it took me so long to get back to you. I'm sure at this point that the problem has resolved itself. If swelling continues to get worse, it seems to be indicative of an overly allergic reaction. All reactions to bug bites technically fall into the realm of allergic reactions, but if the reaction continues to persist and gets worse over time, it can lead to a scary situation. The safest thing is to go back to the hospital. But antihistamines can be used to reduce swelling that's due to an allergic reaction.

betty ann on May 16, 2013:

My son came in the house yesterday and said something bit him so I did what any mother would do, I cleaned the bite and kissed his booboo. This morning I went to get him up and I noticed his hand was swollen to the point he couldn't close his fist. I took him to the hospital and they just dismissed it as an ant bite. As i was putting him to bed a few minutes ago i noticed it had swelled even more and the swelling was workin its way up his arm. As a mother i know there is something else to it. Can anybody help me please???????????

deruffs on January 22, 2013:

I woke up yesterday morning and I two huge bumps on my leg. They are so itchy, red, and I feel burn.

I notice in the middle of the bumps, they are some blisters. I wonder what might caused these?

bobby on November 16, 2012:

I woke up in the middle of the night with my index finger on my left hand itching so bad i had to put ice on it. It swelled up twice it's normal size then i realized my right eye was almost swollen shut. I am really allergic to mosquitos but i'm freaking out thinking maybe it's something different. I'm sitting here anxious as hell waiting for other symptoms, like hives or something as I am allergic to bees as well. I hope one didn't get me in my sleep, i'd be in anaphlaxis i'm sure if it was. who knows though. the swelling in the eye is pretty scary.

Caitlin on August 11, 2012:

my husband has a red bump on him with a black dot in the center. does anyone know what would cause this?

joan sabolek on July 12, 2012:

my bite is big like a 50 cent piece and red with a lite tan center, wonder what type of critter bit me/

Amber on July 08, 2012:

My 3 year old is getting these bite marks they are red whelp like bumps and they keep popping up all over her. We don't have pets and nobody else in the home is having this symptom! I am very aggravated that I can't figure out what is causing these bites. Someone plz help me!

franky on July 05, 2012:

I have a question.what kind of insect has been biting my mom while she's asleep?it leaves no bite marks or nothing she just wakes up wit a lil bump and through out the day it gets enormous the whole section of the part she got bit swells up alot

amber on June 30, 2012:

I have three bug bites on my outer leg right above my ankle. I don't see any puncture marks. But there is a small bump in the middle of each one. They started out small but now are quite larger and almost resemble a bruise. They ate reddish in hcolor. But its also making my ankle swell. It almost looks like I broke it.

Heather on June 26, 2012:

I found a bite yesterday on my knee and it had a white dot on it like it was a pimple so I squeezed it like I normally would a pimple well its swole still its not getting worse but it hurts still and I did see what looked like puncture marks in my leg what could this be and will it go away someone please let me know message me on yahoo with any answers. Untouchable_foeva thanks

David Walli from Northern Minnesota on June 18, 2012:

Lot's of rain in Minnesota means Mosquitos, a full pond, lush green foliage and a lot of water in the creek.

mysterymom on June 15, 2012:

They're probably flea bites which usally appear in multiples. Check and clean carpets, couches, beds, dogbeds and dogs. You can also buy "fleabombs" at pet supply stores. While there please choose some flea prevention/killer for the pooches.

Angelique on June 02, 2012:

I have small red bumps on myself as well as my daughter. We have two dogs. Could it be fleas??

Benji Mester (author) from San Diego, California on May 03, 2012:

Hmm, I'm not really an expert in foreign bugs. I lived in the tropics for a year, in Cambodia, and whenever I woke up with bites all over a certain area, it was usually just a couple of mosquitoes that had gotten into the room.

Lynn on April 29, 2012:

I was out in the country in Panama visiting my grandparents and one morning I woke up with insect bites all across both my legs and each bite had a red dot. No one could figure out what got to me.

Benji Mester (author) from San Diego, California on April 18, 2012:

Yeah, I've heard that. It's pretty nasty.

bed bugs wrong on April 17, 2012:

bed bugs are definitely on the rise in urban environments

Benji Mester (author) from San Diego, California on June 07, 2011:

Hopefully. Cross your fingers :)

David Walli from Northern Minnesota on June 03, 2011:

That is a big mosquito... the bugs are out in Minnesota tonight. as are the frogs. i think that the minnows are still in the pond, eating lots of mosquito larva, I hope.

mark on October 12, 2010:

I once woke up with a bite on my back the size of a nickel. It hurt to touch and was very sensitive. The swelling made it stick out about 2 MMs and when I had someone squeeze it, puse came out.

Two days ago, I woke up and found a similar bite, but only smaller in size. This time it was on my penis!

Benji Mester (author) from San Diego, California on September 14, 2010:

Hmm, well if it doesn't get worse, you should be okay.

cathrine on September 14, 2010:

i have a bite but idont know what type it is and dose not have any holes in it