What Is Urticaria (Hives)?

Table of Contents
View All
Table of Contents

Urticaria (hives) usually starts with a red, itchy patch of skin and develops into a raised welt with clearly defined borders. It is caused by an abnormal immune response. While this may occur as a result of an allergy to a food or medicine, there are often non-allergic causes. Symptoms may come and go quickly or they can be long-lasting. The appearance may be enough for diagnosis, but chronic cases may require allergy testing, a physical challenge, or other tests. Antihistamines are typically used to treat urticaria, although H2 blockers, corticosteroids, antidepressants, and anti-asthma drugs may also be prescribed.

What Is Urticaria?
Verywell / Emily Roberts

Urticaria Symptoms

Urticaria can affect people of any age and may develop on any part of the body, including the palms and soles.

The hives will appear as raised welts (wheals or weals) and will invariably be itchy—some more than others. They can vary in shape and size and will have a clearly defined border. When pressed, the center will "blanch" (turn white).

Symptoms are commonly confused with those of other conditions, but close attention to these defining factors can help distinguish urticaria.

Most hives are acute and self-limited, resolving on their own within 24 to 48 hours. Others may take days or weeks before they fully resolve. During this time, it is not uncommon for the hives to disappear and reappear. Urticaria may sometimes be accompanied by a deep-seated swelling of tissue known as angioedema, most commonly affecting the face, lips, tongue, throat, or eyelids.

Chronic hives can persist for months or even years and may be triggered by stress, heat, cold, and other physical triggers.

Urticaria differs from eczema (atopic dermatitis) in that eczema is characterized by dryness, crusting, cracking, oozing, or bleeding. Hives are not typically described in these ways.


urticaria on legs
Hives on leg.


Broadly speaking, all forms of urticaria are a result of an abnormal immune response.﻿﻿ While an allergy is the most common example, it is not the only cause.

Certain chronic forms of urticaria are believed to be triggered by an autoimmune response.

Allergy-Induced Urticaria

Allergy-induced urticaria occurs when the immune system responds abnormally to an otherwise harmless substance and releases a chemical known as histamine into the bloodstream. Histamine is an inflammatory substance that causes the symptoms of allergy, affecting the respiratory system, gastrointestinal tract, and skin.

Common triggers of allergy-induced urticaria include food (including shellfish, eggs, and nuts), drugs (including aspirin and antibiotics), and insect bites (especially bees and fire ants).

Chronic Idiopathic Urticaria

Chronic urticaria is often idiopathic and may be worsened in times of stress. The exact pathway of the condition is unknown. In some patients, autoantibodies (immune proteins that target the body's own cells) are found in blood, but these autoantibodies are not necessarily disease-causing. Testing for these autoantibodies is generally discouraged because positive results do not diagnose chronic urticaria or help in routine treatment decisions.

While the instigating cause of chronic urticaria may be different ​from allergy-induced urticaria, the outcome will be the same (albeit longer-lasting). Women tend to be affected more than men.

In addition to stress, common physical triggers include exposure to cold, heat, sunlight, pressure, vibration, water, and friction. Certain types of exercise-induced urticaria occur only in tandem with a food allergy. In other words, exercise alone will not cause a reaction, and food alone will not cause a reaction, but in this form of allergy, eating a specific food (e.g. wheat) and then exercising may cause a reaction.

Other Causes

Infections and diseases like hepatitis, chronic kidney disease, lymphoma, and any number of autoimmune disorders (including lupus, Hashimoto's thyroiditis, and rheumatoid arthritis) may also manifest with acute or chronic hives.


Urticaria can usually be diagnosed based on a review of your medical history and the characteristic appearance of the rash. Lab tests and imaging are generally not required unless an underlying cause is suspected, such as cancer.

The severity of an eruption can be classified based on an assessment tool called the urticaria activity score (UAS). For this, a patient subjectively rates the two primary symptoms—the wheals and the itchiness (pruritus)—on a scale of 0 (low disease activity) to 3 (severe disease activity). Having a maximum score of 6 often means that a patient requires further treatment, particularly if the symptoms are chronic.

If further testing is needed, it may involve one of the following:

  • Allergy testing may be recommended if you’ve had a severe hypersensitive reaction to food, medications, or an insect sting. A skin test or a specific IgE test are the two most common forms of allergy testing.
  • Physical challenge tests are used to confirm that your chronic hives are physically induced. This involves the application of the suspected stimuli—such as ice, heat, vibration, light, or friction—to the skin. Exercise testing may also be used.
  • Skin biopsy (the removal of a tissue sample for lab evaluation) is only indicated if the hives fail to improve and no other cause can be found. Unless there is some unusual explanation for the wheals, a biopsy of a hive will usually not reveal anything abnormal.


Most acute hives will resolve on their own within a few days and the itching and swelling may be eased with a wet, cool compress.

Treatment for hives that don't resolve naturally depends on the cause and symptoms. Some cases may take up to several weeks and require oral antihistamines to help alleviate the symptoms. Over-the-counter antihistamines such as Allegra (fexofenadine), Claritin (loratadine), and Zyrtec (cetirizine) usually provide ample relief.

 Stronger antihistamine drugs may be obtained by prescription.

If antihistamines are adequate for providing relief, other drugs may be added or substituted, particularly if the cause is non-allergic.

Among them:

  • H2 blockers, such as Pepcid (famotidine) and Tagamet (cimetidine), can be used in combination with antihistamines to reduce vascular swelling.
  • Corticosteroids, like Prednisone, can dampen the immune response and quickly reduce itching and swelling. While this can be useful for a few days, it is generally not recommended long-term due to the potential for significant side effects.
  • Leukotriene modifiers like Accolate (zafirlukast) and Singulair (montelukast) are commonly used to treat asthma but are also used off-label to treat certain forms of chronic idiopathic urticaria that have not improved with antihistamines alone.
  • Doxepin is a tricyclic antidepressant that also acts as a powerful antihistamine when used in low doses.
  • Xolair (omalizumab) is an injectable monoclonal antibody that is effective for treating chronic forms of urticaria that have not responded to antihistamines.

A Word From Verywell

While hives can be unsightly and uncomfortable, they usually aren't serious. However, if they start to interfere with your quality of life, ask your healthcare provider for a referral to an allergist who can perform tests to pinpoint the cause.

In rare cases, hives may develop as part of a potentially life-threatening allergy known as anaphylaxis. If your hives are accompanied by facial swelling, difficulty breathing, rapid heartbeat, vomiting, and/or confusion, call 911 or have someone rush you to the nearest emergency room. If left untreated, anaphylaxis can lead to shock, coma, heart or respiratory failure, and death.

Was this page helpful?
19 Sources
  1. Deacock SJ. An approach to the patient with urticariaClin Exp Immunol. 2008;153(2):151–161. doi:10.1111/j.1365-2249.2008.03693.x

  2. Kanani A, Betschel SD, Warrington R. Urticaria and angioedemaAllergy Asthma Clin Immunol. 2018;14(Suppl 2):59. doi:10.1186/s13223-018-0288-z

  3. Katelaris CH, Peake JE. 5. Allergy and the skin: eczema and chronic urticaria. Med J Aust. 2006;185(9):517-22.

  4. Goh CL, Tan KT. Chronic autoimmune urticaria: where we stand?Indian J Dermatol. 2009;54(3):269–274. doi:10.4103/0019-5154.55640

  5. Greaves MW, Sabroe RA. ABC of allergies. Allergy and the skin. I--UrticariaBMJ. 1998;316(7138):1147–1150. doi:10.1136/bmj.316.7138.1147

  6. Ograczyk-Piotrowska A, Gerlicz-Kowalczuk Z, Pietrzak A, Zalewska-Janowska AM. Stress, itch and quality of life in chronic urticaria femalesPostepy Dermatol Alergol. 2018;35(2):156–160. doi:10.5114/ada.2018.75237

  7. Justiz Vaillant AA, Zito PM. Immediate Hypersensitivity Reactions. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing. Available from: https://www.ncbi.nlm.nih.gov/books/NBK513315/

  8. Schoepke N, Doumoulakis G, Maurer M. Diagnosis of urticariaIndian J Dermatol. 2013;58(3):211–218. doi:10.4103/0019-5154.110831

  9. Hollis K, Proctor C, McBride D, et al. Comparison of Urticaria Activity Score Over 7 Days (UAS7) Values Obtained from Once-Daily and Twice-Daily Versions: Results from the ASSURE-CSU StudyAm J Clin Dermatol. 2018;19(2):267–274. doi:10.1007/s40257-017-0331-8

  10. Gleich GJ, Yunginger JW. The radioallergosorbent test: a method to measure IgE antibodies, IgG blocking antibodies, and the potency of allergy extractsBull N Y Acad Med. 1981;57(7):559–567.

  11. Komarow HD, Arceo S, Young M, Nelson C, Metcalfe DD. Dissociation between history and challenge in patients with physical urticariaJ Allergy Clin Immunol Pract. 2014;2(6):786–790. doi:10.1016/j.jaip.2014.07.008

  12. Ying S, Kikuchi Y, Meng Q, Kay AB, Kaplan AP. TH1/TH2 cytokines and inflammatory cells in skin biopsy specimens from patients with chronic idiopathic urticaria: comparison with the allergen-induced late-phase cutaneous reaction. J Allergy Clin Immunol. 2002;109(4):694-700.

  13. Lee EE, Maibach HI. Treatment of urticaria. An evidence-based evaluation of antihistamines. Am J Clin Dermatol. 2001;2(1):27-32.

  14. Fedorowicz Z, Van zuuren EJ, Hu N. Histamine H2-receptor antagonists for urticaria. Cochrane Database Syst Rev. 2012;(3):CD008596.

  15. Godse K, Bagadia A, Patil S, Nadkarni N, Gautam M. "Busting" urticaria with a "burst" of steroidsIndian J Dermatol. 2014;59(6):618–619. doi:10.4103/0019-5154.143546

  16. de Silva NL, Damayanthi H, Rajapakse AC, Rodrigo C, Rajapakse S. Leukotriene receptor antagonists for chronic urticaria: a systematic reviewAllergy Asthma Clin Immunol. 2014;10(1):24. doi:10.1186/1710-1492-10-24

  17. Özkaya E, Babuna kobaner G, Yılmaz Z, Kutlay A. Doxepin in difficult-to-treat chronic urticaria: A retrospective, cross-sectional study from Turkey. Dermatol Ther. 2019;32(4):e12993.

  18. Naaman S, Sussman G. Chronic idiopathic urticaria: treatment with omalizumab. Skin Therapy Lett. 2014;19(6):1-4.

  19. Benelli E, Longo G, Barbi E, Berti I. Anaphylaxis in atypical cold urticaria: case report and review of literatureItal J Pediatr. 2018;44(1):135. doi:10.1186/s13052-018-0578-6

Additional Reading