What Causes Itchy Bumps on Skin That Aren’t Mosquito Bites?

Medically reviewed by Leah Ansell, MD

Many conditions that look like mosquito bites can cause itchy bumps on the skin. They include other types of bug bites, infections, or skin irritations. Just about everyone at some point will have an itchy bump on their skin that isn't from a mosquito bite. This article will cover seven common causes of itchy mosquito-like bumps and how to treat them.

What Causes Itchy, Mosquito-Like Bumps?

Many causes create itchy, mosquito-like bumps. Below are seven conditions that include both bug bites and skin conditions that cause bumps that could be misdiagnosed as mosquito bites.

Flea Bites

Fleas are tiny brown bugs the size of a pinhead. They feed on the blood of warm-blooded animals, including humans. Typically found on household pets like cats and dogs, the fleas can jump from the pets to humans.

Flea bites are itchy small, red bumps. They are usually found in groups of three or four on the body.

To treat flea bites, wash the area with soap and water. Apply calamine lotion or an anti-itch cream like over-the-counter hydrocortisone. Try not to scratch the flea bites, as this can cause them to become infected.

Related: Overview of Insect Bites and Stings

Hives

Hives, also known as urticaria, are raised, itchy, red patches or bumps on the skin. There can be just a few bumps or large red patches on the skin.

Hives have many different causes they can include:

• Infections: Viral infections cause more than 80% of hives in children.

• Medications: Antibiotics, nonsteroidal anti-inflammatory drugs (NSAIDs) like Advil or Motrin (ibuprofen), and aspirin are all known to cause hives.

• Insect bites and stings: Bees, wasps, and fire ants are some insects that can cause hives after a sting.

• Allergies: Food allergies like milk, eggs, and soy can cause hives within 30 minutes of consuming the food.

• Stress: When the body is under stress, it can cause a stress rash or hives to form as the immune system responds to the changes.

Hives tend to resolve within a few days. To relieve the itching, apply a cold washcloth to the area or use an anti-itch cream. Try not to scratch the hives and avoid things that trigger the hives.

Bed Bugs

Bed bugs are tiny insects the size of a poppy seed. They feed on the blood of humans. Bed bugs hide out in dark areas where humans sleep. This includes mattresses, bedding, couches, and box springs. During the night, bed bugs crawl onto humans to feed. They inject a substance into the skin when feeding to prevent people from feeling the bite.

Bed bug bites appear as very itchy welts in a cluster of three to five spots. These spots can form a zigzag pattern on the body. There may also be tiny spots of blood on the person's bedding.

Treating bed bug bites can typically be done at home. Start by washing the bites with soap and water. Then apply an anti-itch cream. The bites should heal within one to two weeks.

The bedding and clothing that has been in the room with the bedding will also need to be treated to kill the bed bugs or be sealed and discarded.

Contact Dermatitis

Contact dermatitis is a skin rash that occurs when the skin comes into contact with an irritant or allergen. Common causes include plants, chemicals, jewelry, and cosmetic fragrances.

A contact dermatitis rash can vary in appearance. It can appear as a red, itchy patch on the skin or as small itchy, fluid-filled blisters.

The best way to prevent contact dermatitis is to avoid the triggers causing the rash. To manage the symptoms until the rash has healed apply a cool compress and use calamine lotion to soothe the itch.

In some cases, contact dermatitis may require you to use a corticosteroid prescription from a healthcare provider.

Scabies

Scabies is an itchy rash caused by the human itch mite. The mite burrows under the top layer of skin to feed and live. Mites are transmitted from human to human through direct skin contact. They are commonly seen in long-term care facilities.

The scabies rash looks like small red bumps. These bumps tend to form in a line and are itchy. If this is the person's first time developing scabies, it will take two to six weeks for symptoms to start. However, if the person has already had scabies, the symptoms will begin within one to four days.

Scabies needs to be treated with a prescription from a healthcare provider. Not only does the person who has scabies need to be treated, but so does everyone who lives with or has sexual contact with the person.

When starting the scabies prescription, make sure to clean the house, vacuum rugs and carpets, and change the bedding. Follow the healthcare provider's instructions on how to use the medication for best results.

Dyshidrotic Eczema

Dyshidrotic eczema, also known as pompholyx, is a skin condition that causes small, incredibly itchy bumps on the hands or feet. The bumps are fluid-filled blisters that usually last for three to four weeks.

There are so many causes of dyshidrotic eczema it can be hard to find a specific trigger. Heat, stress, sweat, nickel, cosmetics, and soap are all common causes.

To treat dyshidrotic eczema, apply cool compresses, anti-itch creams, and moisturize the skin. In some cases, a prescription medication may be necessary.

Guttate Psoriasis

Guttate psoriasis is a type of psoriasis (an autoimmune skin condition) that typically affects children. However, it can be seen in people of all ages. It appears as small, red, round raised patches on the skin. These patches can be itchy.

Guttate psoriasis is usually triggered by a streptococcal (strep) infection.

To treat guttate psoriasis, use an anti-itch cream, moisturizers, lotions that have coal tar, or a prescription medication from a healthcare provider like cyclosporine and methotrexate.

A healthcare provider may also suggest using phototherapy, which uses ultraviolet (UV) light to treat psoriasis.

Long COVID (Long-Haulers) Skin Rash

People who have had COVID-19 can develop a skin rash. The rash may be hives with itchy bumps. A healthcare provider can help a person determine if their rash is from a COVD-19 infection or from another source.

Identifying What’s Triggering Itchy, Mosquito-Like Bumps All Over Body

With so many causes of itchy, mosquito-like bumps, it can be hard to identify the source. The common sources are insect bites, previous illness, or contact with a skin irritant or allergen (a normally harmless substance that provokes an allergic reaction).

If you cannot narrow down the cause, you should contact a healthcare provider. A healthcare provider can review your health history and determine if testing is necessary. Having a correct diagnosis will help you get started on the right treatment and provide faster healing.

When to Call Pest Control

Itchy bumps on the skin rarely require someone to contact pest control. The one exception is for bed bugs. Bed bugs can be removed without pest control, but it can be difficult since they are such good hiders and may be resistant to pesticides. A pest control company will have the right equipment and know where to look to remove the bed bugs.

How to Stop Itching, Mosquito-Like Bumps on Skin

To stop itchy, mosquito-like bumps on the skin, the first step is to avoid the cause. Prevention will be the best medicine for these bumps.

Other ways to stop the itching are:

• Applying a cool compress

• Using anti-itch creams like hydrocortisone

• Covering the bumps with calamine lotion

• Avoiding tight clothing over the bumps

• Moisturizing

A healthcare provider can prescribe stronger anti-itch creams or may suggest using an antihistamine.

Summary

There are several causes of itchy mosquito-like bumps on the skin. It can be from insect bites, infections, or skin conditions. Most of the time, these bumps can be treated at home. When symptoms are too severe or do not resolve, it's time to contact a healthcare provider. You may need a prescription medication to target the cause and eliminate the itch.