What is urticaria?

Urticaria is a type of rash which is made up of wheals. (A wheal is a temporary raised area of the skin which is often itchy.) Because the rash looks like that which is caused by stinging nettles, urticaria is sometimes referred to as nettle rash.

It can also be known as hives or welts.

What causes urticaria?

In some cases, the cause of urticaria is unknown. When the cause is known, it is often due to an allergic reaction of some sort. Foods such as nuts and seafood for example, can cause some people to break out in hives. Other examples include:

What does urticaria look like?

Urticaria is a rash that is made up of wheals, which look like little bumps on the skin. They are usually red in colour, and can have a whitish top.

The rash can be of different shapes and sizes, and is often itchy.

Urticaria most often affects the arms, legs, face and external genitalia, although they can appear anywhere on the skin.

Can I get urticaria more than once?

Yes. Urticaria can recur, or it can be a one-off.

How long does urticaria last?

Urticaria may only last a few hours. However sometimes the rash disappears, only to return later in a different place. In some cases, urticaria can recur weeks after the initial rash.

Should I seek medical treatment if I get urticaria?

It depends. If you get acute urticaria, the rash will begin within an hour of exposure to the allergen or physical stimulus. (For this reason it is often possible to identify what is causing the rash.) Urticaria will then occur every time the person comes into contact with that allergen, such as a particular plant or stimulus, for example a belt that is too tight. In such cases, avoidance of the allergen or stimulus may be all that is needed; therefore medical treatment may not be required.

However if you do not know what is causing the urticaria, or if the rash persists beyond a few hours, you should visit your doctor.

A person may have chronic urticaria, in which the rash lasts for weeks. If your rash is persistent, visit your doctor for advice on possible treatments.

If you discover that you are allergic to insect bites or bee stings, be aware of the precautions you need to take, such as having a bee-sting kit with you, especially during summer outings.

My child sometimes gets urticaria during the summer. A friend of mine told me that she will grow out of this. Is this true?

In some cases it can be true. In many cases, the tendency to develop urticaria decreases as a person gets older.

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