What do hives look like

By Isabella Storyclaire

last updated September 16, 2024

Contributions sourced from

Hives: Pictures, Causes, and How to Treat Them

Hives typically occur as an allergic response to something in your environment or something you ate. But they may sometimes happen because of an underlying health issue.

Hives, also known as urticaria, are itchy, raised welts that are found on the skin. Theyre usually red, pink, or flesh colored on lighter skin and may be flesh colored or slightly lighter or darker than your skin tone on brown or black skin.

Sometimes they sting or hurt. In most cases, hives are caused by an allergic reaction to a medication or food or are a reaction to an irritant in the environment.

In many cases, hives are an acute (temporary) problem that may be alleviated with allergy medications. Most rashes go away on their own. However, chronic (ongoing) cases, as well as hives accompanied by a severe allergic reaction, are larger medical concerns.

Hives can develop in different patterns and may or may not cover large areas of skin. nidchita/Shutterstock

These small bumps indicate a possible allergic reaction or skin sensitivity. konmesa/Getty Images

Hives can have a variety of shapes, sizes, and colors. konmesa/Shutterstock

Hives are usually caused by an allergic reaction to something that you have encountered or swallowed. When you have an allergic reaction, your body begins to release histamines into your blood. Histamines are chemicals your body produces in an attempt to defend itself against infection and other outside intruders.

In some people, histamines can cause swelling, itching, and many of the symptoms that are experienced with hives. In terms of allergens, hives can be caused by factors such as pollen, medications, food, animal dander, and insect bites.

Hives might also be caused by circumstances besides allergies. Its not uncommon for people to experience hives as the result of stress, tight clothes, exercise, illnesses, or infections.

Its also possible to develop hives as the result of excessive exposure to hot or cold temperatures or from irritation due to excessive sweating. Because there are several potential triggers, many times the actual cause of hives cant be determined.

People who are known to have allergies are more likely to get hives. You may also be at risk of developing hives if youre taking medication or if youre unknowingly exposed to things you may be allergic to, such as food or pollen. If youre already ill with an infection or a health condition, you may be more vulnerable to developing hives.

The most noticeable symptom of hives is the welts that appear on the skin. Welts may be red but can also be the same color as your skin. They can be small and round, ring-shaped, or large and of random shape. Hives are itchy, and they tend to appear in batches on the affected part of the body. They can grow larger, change shape, and spread.

Hives may disappear or reappear over the course of the outbreak. Individual hives welts can last anywhere from half an hour to a day. Hives may turn white when pressed. Sometimes the hives may change shape or form together and create a larger, raised area.

Hives can occur in a variety of places on the body. Call 911 or get medical attention immediately if you develop a hives outbreak around your throat or on your tongue or have trouble breathing along with hives.

Hives can occur in response to an allergic reaction or may not have an identifiable cause.

Allergic reactions

The most common causes of hives are allergic reactions. These can be caused by any allergen you might be sensitive to, including:

foods (such as nuts, milk, and eggs)
pet dander
pollen
dust mites
insect bites or stings
medications (primarily antibiotics, cancer drugs, or ibuprofen)

Mild cases of hives caused by allergies are typically treated with long- or short-term allergy medications and avoidance of the trigger.

Anaphylaxis

Anaphylaxis is a severe, life threatening allergic reaction. In this condition, hives are often accompanied by breathing difficulties, nausea or vomiting, severe swelling, and dizziness. Call 911 or your local emergency services immediately if you suspect youre experiencing anaphylaxis.

Chronic hives

Chronic hives are ongoing cases that dont necessarily have an identifiable cause. Also called chronic urticaria, this condition is marked by recurring hives that can interfere with your daily life. Chronic cases can last between weeks to several months or years.

You may suspect chronic hives if you have welts that dont go away within 6 weeks. While not life threatening, this form of hives can be uncomfortable and difficult to treat. Chronic hives may also be a symptom of an underlying health problem, such as:

an autoimmune disorder
celiac disease
lupus
type 1 diabetes
rheumatoid arthritis
thyroid disease

Dermatographism

This form of acute hives is considered mild. Excessive scratching or continuous pressure on the skin causes it. Dermatographism usually clears up on its own in a short period of time without treatment.

Temperature-induced hives

Sometimes changes in temperature can induce hives in people who are sensitive to such changes. Cold-induced hives may occur from cold water or air exposure, while body heat from physical activity may cause exercise-induced hives. Exposure to sunlight or tanning beds may also bring about solar hives in some people.

Infection-induced hives

Both viral and bacterial infections can cause hives. Common bacterial infections causing hives include urinary tract infections and strep throat. Viruses that cause infectious mononucleosis (mono), hepatitis, and colds often cause hives.

The first step in getting treatment is to figure out if you actually have hives. In most cases, a doctor will be able to determine if you have hives from a physical exam. Your skin will show signs of the welts that are linked with hives.

A doctor may also perform blood tests or skin tests to find out what may have caused your hives especially if your hives were the result of an allergic reaction.

You may not need prescription treatment if youre experiencing a mild case of hives not related to allergies or other health conditions. In these circumstances, a doctor might suggest that you find temporary relief by:

Anaphylaxis is a medical emergency that needs to be treated immediately by a physician. If you think you may be experiencing anaphylaxis, contact 911 or your local emergency services.

Simple changes to your lifestyle may be able to help you prevent hives from reoccurring in the future. If you have allergies and you know which substances are likely to cause an allergic reaction, a doctor will suggest that you avoid any possible exposure to these factors. Allergy shots are another option that may help you reduce the risk of experiencing hives again.

Avoid being in high humidity areas or wearing tight clothing if you have recently had a hives outbreak.

Below are some of the most commonly asked questions about hives.

Are hives contagious?

No, hives are not contagious and cant spread from one person to another.

Do hives mean Im allergic to something?

In many cases, hives are the result of an allergic reaction to something you have been exposed to, such as certain medications or pollen. It could also be caused by an infection, stress, or wearing clothes that are too tight. If you have hives that persist for more than a few days, contact a doctor to see if an allergy test is needed to determine the cause of your symptoms.

How long do hives last?

A hives outbreak can last anywhere from several hours to up to a week or two. If the hives are the result of an allergic reaction, they may last longer and require medical treatment. In some cases, chronic hives can last for months or even years. Talk with a doctor if you experience hives that dont go away on their own.

Are there any home remedies for hives?

Yes, there are several home remedies that may help alleviate the symptoms of hives. Taking an antihistamine is one option, as well as taking a cool or lukewarm bath with colloidal oatmeal or baking soda. Avoid hot water, as this may aggravate the hives. Also, try to avoid any potential irritants or allergens that may have caused the hives in the first place.

Although hives can be itchy and uncomfortable, usually theyre not severe and will disappear after a period of time. However, be aware that as some hives go away, new ones may pop up.

Mild cases of hives are considered harmless. Hives can be dangerous if you are having a serious allergic reaction and your throat is swelling. Prompt treatment for a severe case of hives is important for a good outlook.

Hives: Signs and symptoms

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Hives Symptoms: What They Look Like

Hives are characterized by red or pale-colored welts on the skin, which typically come and go throughout the day, says Sourab Choudhury, DO, a dermatologist and the chief medical officer at the Dermatology Specialists, a private dermatology practice in New York City. Sometimes they itch, burn, or sting.

Usually the welts will be surrounded by clear edges. They may look similar to bug bites, but hives generally will appear and disappear more quickly. They may itch, sometimes severely, and theyre not always the same size or shape. They may be as small as the tip of a pen or as large as a dinner plate. (4) When you press the center of a hive bump on the skin, it likely will turn from red to white, which is known as blanching. (2,3)

Hives may appear on the body grouped together and take over a large area of the skin, or as a couple of individual welts that show up here and there. (4) They can appear anywhere on the body, though some people get them in the same spot over and over again (usually as a result of a specific trigger). (4)

Generally, youll know you have hives simply by seeing the hives themselves. If you experience other symptoms, such as swelling in the eyes, lips, or inside of the throat, or if you have trouble breathing, you should call 911 or see a doctor immediately, says Sapna Palep, MD, a dermatologist at Spring Street Dermatology in New York City. These symptoms indicate you may be experiencing a serious allergic reaction called anaphylaxis. (5)

Hives and angioedema

Overview

Hives

Illustration of hives on different skin colors. Hives can cause swollen, itchy welts. Hives is also called urticaria.

Angioedema

Illustration of angioedema on different skin colors. Angioedema causes swelling in the deeper layers of skin, often of the face and lips. It often goes away within a day.

Hives also known as urticaria (ur-tih-KAR-e-uh) is a skin reaction that causes itchy welts that range in size from small spots to large blotches. Hives can be triggered by many situations and substances, including certain foods and medications.

Angioedema can arise with hives or alone. It causes swelling in the deeper layers of skin, often around the face and lips. Short-lived (acute) hives and angioedema are common. Most times, they are harmless, clear up within in a day and don't leave any lasting marks, even without treatment. Hives that last longer than six weeks are called chronic hives.

Hives and angioedema are usually treated with antihistamine medication. Angioedema can be life-threatening if swelling of the tongue or in the throat blocks the airway.

Symptoms

Hives

The welts associated with hives can be:

Skin-colored, reddish on white skin, or purplish on black and brown skin
Itchy, ranging from mild to intense
Round, oval or worm-shaped
As small as a pea or as large as a dinner plate

Most hives appear quickly and go away within 24 hours. This is known as acute hives. Chronic hives can last for months or years.

Angioedema

Angioedema is a reaction similar to hives that affects deeper layers of the skin. It can appear with hives or alone. Signs and symptoms include:

Welts that form in minutes to hours
Swelling, especially around the eyes, cheeks or lips
Mild pain and warmth in the affected areas

When to see a doctor

You can usually treat mild cases of hives or angioedema at home. See your health care provider if your symptoms continue for more than a few days.

If you think your hives or angioedema was caused by a known allergy to food or a medication, your symptoms may be an early sign of an anaphylactic reaction. Seek emergency care if you feel your tongue, lips, mouth or throat swelling or if you're having trouble breathing.

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Causes

For most people who experience acute hives and angioedema, the exact cause can't be identified. The conditions are sometimes caused by:

Foods. Many foods can trigger reactions in people with sensitivities. Shellfish, fish, peanuts, tree nuts, soy, eggs and milk are frequent offenders.
Medications. Many medications may cause hives or angioedema, including penicillins, aspirin, ibuprofen (Advil, Motrin IB, others), naproxen sodium (Aleve) and blood pressure medications.
Airborne allergens. Pollen and other allergens that you breathe in can trigger hives, sometimes accompanied by upper and lower respiratory tract symptoms.
Insect bites and infections. Other causes of acute hives and angioedema are insect bites and infections.

Risk factors

Hives and angioedema are common. You may be at increased risk of hives and angioedema if you:

Have had hives or angioedema before
Have had other allergic reactions
Have a family history of hives, angioedema or hereditary angioedema

Complications

Severe angioedema can be life-threatening if swelling of the tongue or in the throat blocks the airway.

Prevention

To lower your likelihood of experiencing hives or angioedema, take the following precautions:

Avoid known triggers. If you know what has triggered your hives, try to avoid that substance.
Bathe and change your clothes. If pollen or animal contact has triggered your hives in the past, take a bath or shower and change your clothes if you're exposed to pollen or animals.

Oct. 27, 2023