Urticaria

Urticaria is a rash that occurs on the skin and is characterized by the appearance of raised, itchy bumps.

Last Updated: February 21, 2024

Urticaria is commonly referred to as hives, weals, welts, or nettle rash. The condition might manifest locally or cover huge regions of the body.

There are two types of urticaria. Hives that last less than six weeks are called acute urticaria. It is chronic urticaria when it occurs more than twice a week and lasts longer than six weeks.

Urticaria affects about 20% of the population at some point in their lives. Chronic urticaria affect between 1% and 3% of the population.

Urticaria happens because the body releases histamine. It is a normal body reaction when it encounters allergens such as food, insect bite/sting, cold/heat exposure, infection, and drugs like NSAIDs or antibiotics.

Signs and symptoms of acute urticaria are the following:

  • Rough, raised patches on the skin. This will appear red in fair skin tone;
  • The center of the lesions turns white when pressed;
  • Itchy skin;
  • Angioedema or when the skin swells up;
  • Lip, eye, and pharyngeal swelling with pain.

Both chronic and acute hives might look similar, with red, itchy, swollen, raised welts that become lighter in the center and when pressed. Chronic urticaria, on the other hand, will:

  • Change in size and form;
  • Show up, vanish, and then resurface at regular intervals (at least every few days) for extended periods (months or years);
  • Coincide with the presence of heat, exertion, or stress.

In the case of acute hives, allergy tests can help determine the cause of the reaction. Some allergy tests that can help determine the cause of hives are the following:

  • Skin test. Doctors do skin tests by applying various allergens to the patient's skin and observing the patient's reaction to each. A positive result will show redness or swelling on the skin, meaning being allergic to an allergen;
  • Blood test. Testing the blood can reveal the presence of specific antibodies. Antibodies are produced within your body to combat allergens. Hypersensitivity reactions like hives and swelling can occur if your body has excessive antibodies.

Treatment

Hives typically clear up on their own without medical intervention. However, the following are prescribed if symptoms persist:

  • Antihistamines like diphenhydramine which reduces itching and swelling;
  • Allergic shots are for chronic hives. Those who suffer from severe allergies tend to produce an abundance of the immune system antibody IgE. Allergic shots will inhibit this production of IgE.

The following are examples of additional medications doctors use for urticaria:

  • Hydrocortisone;
  • Corticosteroids such as prednisone when antihistamines and topical steroids are ineffective;
  • Epinephrine to avoid anaphylaxis, a potentially fatal condition caused by severe acute allergic reactions.

It is also possible to treat hives at home by taking a cool bath or shower, dressing in loose clothing, and applying cold compresses.

In acute urticaria

After identifying the specific allergens from a skin test, the following can be done:

  • Get rid of certain foods from your diet;
  • Lessen your exposure to allergens in the air;
  • Switch to fragrance- and dye-free soaps and detergents;
  • Stay away from temperature swings;
  • When feeling overwhelmed or worried, have a few minutes to unwind;
  • Dress in lightweight, loose-fitting garments

Some of the steps above may be done in chronic urticaria.

In chronic urticaria

Some research suggests that chronic hives may not be preventable. It is possible that the root cause cannot be identified. Even more probable that they are a symptom of a more serious immune system disorder.

References

NHS Inform (2022). Urticaria (hives). Retrieved December 23, 2022, from https://www.nhsinform.scot/illnesses-and-conditions/skin-hair-and-nails/urticaria-hives

 

Cleveland Clinic (2022). Hives. Retrieved December 23, 2022, from https://my.clevelandclinic.org/health/diseases/8630-hives

Last Updated: February 21, 2024