Urticaria (Hives)

Urticaria, commonly known as hives, is a skin reaction causing raised, itchy welts that can appear suddenly and vary in size and location. It can be acute (resolving within six weeks) or chronic (lasting longer), and is usually triggered by an allergic or other immune reaction.

• Raised, red or skin-coloured welts that are intensely itchy
• Welts that can change size, shape, and location over hours, often disappearing from one area and appearing in another
• Swelling of deeper skin layers (angioedema) can occur alongside hives, particularly around the eyes, lips, or throat
• Rarely, hives can be part of a more serious allergic reaction with breathing difficulty — a medical emergency

• Often triggered by an allergic reaction to a food, medicine, insect sting, or other substance.
• Can also be triggered by infections, physical factors (such as pressure, cold, heat, or sun exposure), or, in chronic cases, may occur without an identifiable trigger.
• Chronic urticaria, lasting more than six weeks, sometimes involves an underlying immune process rather than a specific external trigger.

• Diagnosed clinically based on the characteristic appearance and pattern of the rash.
• A detailed history helps identify possible triggers, particularly for acute urticaria.
• Further investigation is sometimes considered for chronic or recurrent urticaria without an obvious cause, though a specific trigger is often not found.

An antihistamine is the first-line treatment, taken regularly to control itching and reduce new welts, with the dose sometimes increased under medical guidance for more persistent symptoms.

Avoiding any identified trigger helps prevent further episodes.

A short course of oral corticosteroids may be used for severe flares not controlled by antihistamines alone.

Any hives accompanied by swelling of the lips, tongue, or throat, or difficulty breathing, should be treated as a possible anaphylactic reaction and requires immediate emergency care.

Chronic urticaria lasting more than six weeks is generally managed by a specialist, who may consider additional treatments if antihistamines are not sufficient.

• Identify and avoid known triggers where possible.
• Keep a symptom diary to help identify potential triggers for recurrent hives.
• Seek immediate care if hives are accompanied by swelling of the face, lips, or throat, or any breathing difficulty.
• Avoid known trigger medicines and inform health workers of any past reactions before new prescriptions.