Alternative names: Hives, welts, wheals, nettle rash, allergic reaction
Urticaria is a common skin condition that can occur as a single episode (acute urticaria), or less commonly, it may recur multiple times for longer than 6 weeks (chronic urticaria). Urticaria is due to the immune system releasing histamine into the skin. This substances cause the redness, swelling and itching. The rash can last from minutes to hours but often disappears without a trace within 24 hours. A trigger for urticaria can be identified in some cases such as:
Infection, Allergies, Environmental temperature changes, Emotional stress, Food, Medication
Even though the rash of urticaria is identical in appearance to that caused by an allergic reaction, in most cases no obvious cause can be found. This is classed as ‘idiopathic urticaria’.
Urticaria usually appears as a series of raised, red bumps that come up within minutes and can resemble mosquito bites or nettle rash. It can be limited to a small area or span large expanses of the body (see picture). Sometimes there is swelling of the face and eyes (angio-oedema). The rash often resolves over a period of an hour or two, but might last as long as 24 – 36 hours
Hives are usually very itchy which can be a source of much frustration. In chronic cases, the symptoms are often worse in the evenings which can affect quality of sleep. If symptoms are severe it may also affect a person’s ability to carry out simple activities of daily life or work. Some people also find the physical appearance of wheals distressing.
Most cases of acute urticaria get better without treatment and the symptoms can be effectively treated with antihistamines. For long-term urticaria the treatments aim to relieve symptoms rather than act as a cure. Identifying potential triggers is an important first step though usually a specific offender cannot be found. Available treatments include antihistamines, short courses of steroid tablets and in very severe, chronic cases medications to dampen the body’s immune system (such as ciclosporin) can be beneficial.
Our Specialist Dermatologists at the Harley Street Dermatology Clinic can offer effective treatment to patients to help control your symptoms.
For further information please visit the NHS website or see the British Association of Dermatology Patient leaflet