Bug Bites That Blister: What to do?

Skin Care article posted on Jul 27, 2011 by Joséphine Beck, Digestive Care Advisor

Bug bites are, for the most part, annoying but harmless. The response to a sting or bite from insects is variable and depends on a variety of factors. Most bug bites and stings result in pain, swelling, redness, and itching to the affected area. But these bites can sometimes result in blistering. Why do blisters form? What can you do to treat a bite that blisters?

Blisters can develop due to allergies to bug bites
Types of bites that may cause blisters
What to do when bug bites blister?
Other useful links about bug bites

Blisters can develop due to allergies to bug bites

Many of the mosquito saliva proteins can cause immune reactions, including allergic reactions. Severe reactions are not common but they may result in blistering rashes, bruises, or large areas of swelling at the bite sites. People who experience extremely large areas of swelling after a mosquito bite have been dubbed as having "Skeeter Syndrome."

In rare situations, some people may experience anaphylaxis after being bitten by mosquitoes. Other people may have experienced whole body urticaria and angioedema (hives and swelling), or worsening of asthma symptoms after being bitten. Typically, these symptoms occur within minutes after a mosquito bite, compared to Skeeter Syndrome, which may take hours to days to occur.

For more information on mosquito allergy, see: Reactions to Mosquito Bites by Daniel More, MD.

Types of bites that may cause blisters

Insect bites:

If you are particularly sensitive to insect bites, you may develop bullae (fluid-filled blisters) or weals (circular, fluid-filled areas surrounding the bite).

Tick bites:

Tick bites are not usually painful and sometimes only cause a red lump to develop where you were bitten. However, in some cases they may cause swelling, itchiness, blistering, and bruising.

Spider bites:

Spider bites typically form a blister or pustual on top of the bite within 1-2 days.
Brown recluse spider bites don't cause problems for most people. But in a small percentage of cases, the swelling may form a blister. If this happens, a dark, scabby material called eschar may cover the blister within a week after the bite. If you suspect this bite, see your doctor. This ulcerated area can continue to enlarge if not treated promptly by a physician.

Mites:

Mites cause very itchy lumps to appear on the skin and can also cause blisters.

Bee stings:

Bees are the most typical stinging insects (this includes wasps, hornets, and yellow jackets). Pain from a bee, hornet or wasp sting is immediate, with rapid swelling, redness, warmth and itching at the site of the sting. Blisters may also occur.

What to do when bug bites blister?

Most bites get usually better on their own, but it can sometimes take a couple of months. So it's always a good idea to see a doctor for proper treatment.

Blisters do not often cause pain unless they rupture, exposing the new skin underneath. If possible, use an adhesive bandage to protect the blistered area.
Don't scratch the bite because this can make the bite more itchy and swollen and increase the chance of a secondary infection.

Plantain

Plantain may be used externally to treat blisters and insect bites. A poultice of the leaves may be applied to the affected area. For relief from an insect bite, simply shred (or chew) a plantain leaf and hold it on the bite for a few minutes. A plantain ointment can also rapidly relieves itching and swelling.