What Are Hives (Urticaria)?

Created: 10.01.2025 · Last Updated: 26.06.2026 · Category: Dermatology · Prepared by the Academic Hospital Web and Editorial Board.

Hives, medically known as urticaria, are a common skin reaction that appears suddenly as itchy, raised and red or skin-colored welts. The rash may stay limited to one area or spread to different parts of the body.

Hives often improve within a short time. However, recurrent or long-lasting hives, or hives accompanied by swelling of the lips, eyelids, tongue or throat, require medical evaluation.

Important Information: Hives are not contagious. A typical feature is that individual welts usually fade from the same area within 24 hours and may reappear elsewhere.

What Are Hives?

Hives are an itchy, raised skin reaction that can be allergic or non-allergic. Welts may be localized or widespread. They may range from a few millimeters to several centimeters, and sometimes merge to cover larger areas of skin.

One distinguishing feature of hives is that the rash often fades within 24 hours in one location but can reappear in another. Hives are commonly classified as acute when they last less than six weeks and chronic when they persist or recur for more than six weeks.

How Common Are Hives?

Hives are a common skin reaction. Many people experience at least one episode during their lifetime. Even when the rash is short-lived, recurrent or severe episodes should be evaluated for possible triggers.

Are Hives Chronic or Contagious?

Hives are not contagious. They do not spread from person to person through contact, sharing the same environment or using the same objects.

Most cases improve within a few days or weeks. If hives last longer than six weeks or recur frequently, chronic urticaria should be considered and evaluated.

Caution:

  • Hives lasting longer than six weeks require evaluation for chronic urticaria.
  • Shortness of breath, difficulty swallowing, or swelling of the tongue or throat requires urgent medical care.

Symptoms of Hives

Hives usually appear as itchy, red, raised welts on the skin. The rash may appear and disappear throughout the day. Burning may accompany itching. Some people may also develop angioedema, which is swelling around the lips, eyelids, tongue or throat.

Symptom How It May Appear
Raised welts Red, pink or skin-colored raised patches may appear.
Itching It may be mild or severe enough to disturb sleep and daily life.
Changing location Welts may disappear from one area and reappear elsewhere.
Angioedema Swelling may occur around the lips, eyelids, tongue or throat.

Contact us for dermatology evaluation if you have hives-related complaints.

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What Causes Hives?

Hives may have many possible causes. Medicines, infections, foods or additives that cause a personal reaction, pollens, dust and physical triggers may be involved. Physical triggers can include heat, cold, sunlight, water, pressure, sweating and exercise.

Seafood, especially fish and shellfish, may act as allergens in some people. However, food elimination is not needed for every person with hives. Food or medication restrictions should be planned after medical evaluation and history taking.

Important Information: Hives are not always caused by a clear allergy. Infections, medicines, heat or cold exposure, pressure, stress and environmental factors may also trigger hives.

Possible Triggers of Hives

Identifying a trigger can make treatment planning easier. However, in some patients, no clear cause can be found despite evaluation. It may be useful to note when the rash starts, whether it worsens after foods or medicines, and whether it is related to physical triggers.

Trigger Group Examples
Foods Seafood, additive-containing foods, processed foods
Medicines Some pain relievers, antibiotics or medicines that cause a personal reaction
Infections Upper respiratory infections and some viral infections
Physical triggers Heat, cold, sunlight, water, pressure, sweating, exercise
Environmental factors Pollen, dust, chemical contact, insect stings

How Are Hives Diagnosed?

Hives are usually diagnosed by a dermatologist through physical examination and evaluation of symptoms. The duration of the rash, daily pattern, accompanying swelling, medicines used, recent infections and possible food exposures are assessed together.

Advanced testing is not required for every patient. If the doctor suspects an underlying condition, blood tests, allergy tests or additional evaluations may be requested. Testing decisions depend on examination and patient history.

How Are Hives Treated?

If welts and redness continue for several days, recur often or worsen, dermatology evaluation is recommended. If hives are accompanied by angioedema or signs of a severe allergic reaction, emergency care may be needed.

Treatment includes identifying and avoiding possible triggers when possible. If a food or medication is suspected, permanent restriction should not be made without medical evaluation.

Antihistamines often help control itching and rash in many patients. If they are not sufficient, other treatment options may be considered by a dermatologist.

Treatment note: The goal is to reduce itching, control new welts and avoid triggers when identified. Medicine choice and dose plan should be individualized.

When Should You See a Dermatologist?

If hives do not improve within a few days, recur frequently, affect daily life because of itching, or are accompanied by swelling, they should be evaluated by a dermatologist. In chronic urticaria, understanding the course of the disease and possible triggers is as important as suppressing the rash.

Signs that may require urgent evaluation:

  • Shortness of breath, wheezing or chest tightness
  • Rapid swelling of the tongue, throat, lips or face
  • Difficulty swallowing or speaking
  • Dizziness, feeling faint or confusion
  • Widespread rash with vomiting, abdominal pain or poor general condition

Do Not Postpone Hives-Related Complaints

You can book an appointment with Academic Hospital dermatology specialists for personalized evaluation and treatment planning.

Frequently Asked Questions

Are hives contagious?
No. Hives are not contagious. However, infections, medications, foods or environmental factors that trigger hives may vary from person to person.
How long do hives last?
Acute hives often improve within a few days or weeks. Hives that last longer than six weeks or frequently recur should be evaluated as chronic urticaria.
Are hives always an allergy?
Hives may be caused by allergy, but not all hives are allergic. Infections, medicines, stress, heat, cold, pressure and other physical triggers may also cause or worsen hives.
Which doctor should I see for hives?
A dermatologist can evaluate hives. Allergy and immunology consultation may also be requested when needed.
Do hives leave marks?
Typical hives usually disappear from the same area within 24 hours and do not leave scars. Bruising, persistent discoloration, painful rash or peeling should be evaluated for other skin conditions.
Academic Hospital note: You can book an appointment for dermatology evaluation if you have hives, angioedema or recurrent itchy skin rashes.

References

The general information in this article about hives, urticaria symptoms, emergency signs and treatment approach is supported by the following authoritative health sources.

  1. Academic Hospital. Kurdeşen Nedir?
  2. American Academy of Dermatology Association. Hives: Diagnosis and Treatment
  3. Cleveland Clinic. Hives (Urticaria): Causes, Symptoms and Treatment
  4. MedlinePlus. Hives