Written by: A O’Neill, Licensed Pest Control Technician

One person’s immune response will be different from another person’s, but generally, if you don’t have a severe reaction and the bites are not scratched too much, the bed bug bites will begin to fade and heal within 2-3 weeks. If you scratch the bites a lot because of the irritation and itching then you will find they obviously take longer to heal.

Are These Bed Bug Bites?

Unfortunately, there is no definitive way of knowing if the red marks on your body are from bed bugs unless you actually find these blood-sucking insects or evidence of them.

Not even a GP can say for certain if the welts are caused by bed bugs as they look very similar to other insect bites, and are often also confused with hives.

However, there are some tell-tale signs that increase the likelihood of bed bug bites if:

  • You’ve recently traveled and stayed in other accommodation
  • You’ve bought used furniture, such as a bed frame or mattress
  • You’ve woken up to find red welts on your skin that weren’t there when you went to bed
  • Bite marks have occurred on areas of the body that are often exposed when sleeping, such as the face, back, shoulders, neck, arms, hands, and legs
  • Smeared blood or specks of blood on the bedsheets

    Find out how to check for bed bugs in your home.

What Do Bed Bug Bites Look Like?

Bed bug bites commonly look like a bite from a mosquito, flea, or other biting insect resulting in a small and red itchy welt. The welt is usually small in size (2-5mm or around 1/10 inch) and is the response of the body’s immunity reacting to the allergens in the bed bug’s saliva. The welt will have a tiny hole where the bed bug has fed and this is barely visible.

Below are some pictures of bed bug bites. You can see how they can be mistaken for other insect bites or hives. See more images of bed bugs here.

Large welts on arm from bed bug bites
Bed bug bites on arm Credit: James Heilman, MD / CC BY-SA (
Large red welts from bed bug bites on human back
picture of bed bug bites on back James Heilman, MD / CC BY-SA (
Large red welts from bed bug bites on persons back
picture of bed bug bites on back James Heilman, MD / CC BY-SA (
Bedbug bites on face
Bedbug bites on face
Image credit: The original uploader was Andybrookestar at English Wikipedia. [Public domain]
Small red marks bed bugs bite reaction
Image credit: louento.pix CC Licenses/by-nd/2.0/

Being bitten by bed bugs can cause different reactions in different people. Some will have no reaction at all, others will have slight inflammation and irritation, whilst others, although fewer will have a more severe allergic reaction.

Research studies have shown there is often no reaction to the first bite as the body’s immune system hasn’t come into contact with the salivary proteins of the bed bug before, so reactions generally occur after repeated exposure to bites.[1]

People who react more severely to the bites often find the welts are larger and painfully swollen. They can develop blood blisters and intense itching is also common. This can also happen when repeatedly bitten over a period of time. Thankfully, anaphylactic shock is extremely rare.

More severe reactions to bed bug bites can include difficulty breathing, a swollen tongue, fever and, anemia (very rare but can occur with repeated bites). Medical attention is vital for severe reactions.

The symptoms of bed bugs bites can start to show almost straight away in a person who is repeatedly bitten. However, the initial reaction time can range from a few hours to several days after the bite, which makes it hard to pinpoint exactly when and where the incident occurred. Some people, especially the elderly don’t react to bed bug bites at all.

Can You Feel A Bed Bug Bite?

Bed bugs feed on the blood of people mainly at night, although they will come out to feed during the day if they are especially hungry, or their host tends to sleep during the day.

You won’t feel anything when the bed bug bites. They feed by piercing your skin with their elongated mouthpart, or proboscis. The mouthpart itself is very small and has two stylets, one to withdraw blood from a person to feed, and the other to inject an anticoagulant (blood thinner) and an anesthetic in their saliva to numb the area.

The injected substances allow the bed bug to feed for up to 10 minutes uninterrupted. During that time the bed bug can increase in length by up to 50%, and in weight by up to 200% as the photo below shows.[2]

adult bed bug before feeding and elongated body after feeding
adult bed bug before and after feeding

However, it’s the saliva that the bed bug injects that can lead to an allergic dermal reaction which causes the welts. These welts can cause irritation and itching and become infected when excessively scratched.

Bed bug bites can occur in a line, in clusters, or just a single bite on its own. You might have read they occur in threes (breakfast, lunch, and dinner) but this is inaccurate as the images above show.

How Itchy Are Bed Bug Bites?

As mentioned, not everyone will react to the bites so not everyone will find them itchy. But those of us who have a reaction can find the welts give us an irritating itch and are often sore.

If you are hypersensitive to bites the symptoms might be more severe and the itching will almost certainly be more intense.

As tempting as it is, try not to scratch the bites as this might break the skin causing them to bleed or become infected. A secondary infection such as cellulitis can occur when bacteria that live on your skin enters the scratched area. If cellulitis is left untreated, it can lead to a serious infection.

Another reason to not scratch the bites is scarring. The bite itself won’t cause a scar as the bed bug’s mouthpart is too small, but excessive scratching and breaking of the skin can.


What Can I Put On Bed Bug Bites?

If the itching starts to drive you mad, or you just want to get rid of the bites, there are several (over-the-counter, OTC) options that can help:

  • Hydrocortisone cream can be applied to relieve the itching and swelling.
  • Antihistamine cream or pill for helping with the itchiness.
  • Lotions such as aloe vera and calamine lotion will calm the redness and lessen the irritation.
  • Witch Hazel soothes the itching.
  • Ice pack: wrap it in a towel after taking it from the freezer and place it on the welts to reduce redness, swelling, and itchiness. A frozen bag of peas will work just as well as an ice pack.

Always wash the area with soap and water and dry thoroughly before applying any of the above, and always get the advice of a medical professional to find out what is the best treatment option for you.

Although the bites will heal over a couple of weeks, the infestation will grow and you will continue to get more bed bug bites.

The physical symptoms of bed bugs feeding on you are bad enough, but people find the psychological aspect of having them harder to deal with. Many suffer from insomnia and anxiety when they know they have an infestation, and it’s not surprising as the thought of them crawling over you and biting you while you sleep is very unpleasant.

After you’ve identified evidence of bed bugs, you need to act quickly to get rid of them and you can do this yourself (this detailed guide shows you how) if the infestation is in the early stages, or you’ll need to hire an exterminator to prepare a treatment plan to get rid of them for you.


I’ve been in the pest control industry helping people get rid of their unwanted pests for over 20 years, both in the UK and Canada.

As a licensed pest management professional, I’ve seen and treated just about every common household pest, insect, or rodent, you can think of. I’ve seen the damage caused when an infestation has been left too long and has become hard to get rid of.

For this reason, was created. By having honest advice and the right guidance to hand, along with scientific evidence to back up claims, you are given information on the best eradication methods, as well as how to get rid of most pests yourself.