Urticaria (Hives)

What Are urticaria?

Urticaria, also called hives, is a condition in which itchy, raised welts develop on the skin. These welts may appear suddenly, move from one area to another, and often come and go within hours. Some people have short-lived episodes, while others develop chronic urticaria that persists or recurs for weeks to months.

In some patients, swelling deeper in the skin can also occur. This is called angioedema and often affects the lips, eyelids, hands, feet, or other soft tissues.

What causes urticaria?

Urticaria can be classified as either acute (lasting less than 6 weeks) or chronic (persisting for more than 6 weeks). In both cases, the underlying mechanism involves the release of histamine, which causes blood vessels to expand and the skin to swell. While the exact trigger might not always be identified, some common causes include:

Acute Urticaria (<6 weeks):

• Food allergies, commonly from milk, eggs, peanuts, or shellfish

• Allergic reactions to medications, especially antibiotics

• Insect stings or bites

• Viral or bacterial infections

• Environmental factors like cold, heat, or exercise

• Pseudoallergies from certain medications, including aspirin, NSAIDs, opiates, and contrast dyes

• Vaccinations

• Contact with allergens, such as latex

Chronic Urticaria (> 6 weeks):

The exact cause is often unknown, but in roughly half the cases, autoimmune factors play a role. Other possible causes or associations include:

• Chronic infections like H. pylori or bowel parasites

• Autoimmune disorders, such as lupus, celiac disease, or vitiligo

• Thyroid diseases

• Blood disorders

What are the symptoms of urticaria?

Symptoms can include:

• Itchy, raised welts that can vary in size and shape

• Lesions that appear and fade, sometimes in different places over the course of a day

• Swelling of the lips, eyelids, hands, feet, or other areas

• Burning or stinging in some patients

If swelling affects the tongue, throat, or breathing, urgent medical care is needed.

How are urticaria treated?

Treatment depends on whether hives are acute or chronic and how severe symptoms are.

Common treatment approaches include:

• Non-sedating antihistamines, which are usually first-line treatment

• Dose adjustment of antihistamines under physician guidance when needed

• Short courses of other medications in selected flares

• Omalizumab (Xolair) for chronic spontaneous urticaria that does not respond adequately to antihistamines

• Dupilumab (Dupixent) in selected chronic spontaneous urticaria patients

• Remibrutinib (Rhapsido), an oral treatment option for some patients with chronic spontaneous urticaria

The right choice depends on frequency of symptoms, severity, swelling, prior response to treatment, and the overall clinical picture.

How do I prevent hives from worsening?

Helpful strategies can include:

• Taking medications as directed rather than only after symptoms become severe

• Avoiding known personal triggers when they are clear

• Minimizing tight clothing, heat, and other factors that can aggravate itching

• Reviewing new medications, supplements, or recent infections with your provider