Sometimes itching can affect your whole body. This can happen if you have kidney or liver disease or, more commonly, an allergy. Sometimes an allergy can also give you a rash over the whole body.

Itchy skin is usually not serious. But sometimes it can be caused by a serious medical condition. If you are unsure about a rash or itch, see your doctor.

What causes itchy skin?

Common causes of itchy skin are:

• dry skin
• insect bites
• hives
• heat rash
• eczema
• scabies
• psoriasis
• obstetric cholestasis

Dry skin

Your skin can become dry and itchy from many reasons. It can happen in hot or cold, dry weather. It can happen from using soap. Dry skin looks flaky and rough. It’s not usually very itchy or red. Sometimes dry skin can crack. This can be painful.

Insect bites

There will usually be a bump or blister around the bite. The bite area may be red and painful. Sometimes it can be swollen.

Hives

Hives or urticaria is a raised, bumpy rash. It can be red or normal skin colour. It’s very itchy. The rash is often on the chest, abdomen or back but can appear anywhere. The rash will last from a few hours to 24 hours. Then it disappears. It does not leave a scar.

Hives is most commonly caused by an allergy, but it can also be caused by viral infections.

Heat rash

Heat rash looks like little pink or red spots or blisters. They can appear anywhere on your skin. Heat rash is also called miliaria or prickly heat. It’s very common in babies.

Eczema

Eczema causes itchy, red, scaly patches on your skin. The patches are usually on your neck, wrists and in your elbow creases. They can also be behind your knees and in children they are often on the cheeks. Eczema is common in children. It often runs in families who have conditions like allergies, hay fever or asthma. Eczema is also called atopic dermatitis.

Scabies

Scabies are small bugs (mites) that cause a very itchy skin rash. There will be red lumps and threadlike tracks on your skin. These usually appear between your fingers and toes. They can also be seen on the insides of your wrists and in your armpits. Other places that they are found are around your groin and buttocks creases.

Psoriasis

Psoriasis causes thick red, scaly patches on your skin. The scales can be silvery white. The patches are often on your scalp, knees, elbows, and belly button. They can also be found between the buttocks.

Obstetric cholestasis

Obstetric cholestasis is not very common. It usually occurs in the last 4 months of pregnancy. It can cause an all-over itching of the skin. There is not usually a rash. The whole of your body may be affected. This can include the palms of your hands and the soles of your feet.

When you’re pregnant you may feel itchy across your tummy area. This can be due to the skin stretching as your baby grows.

Other causes of itchy skin

Itchy skin can sometimes be caused by certain medicines. You can also get itchy skin from recreational drugs or herbal supplements.

In older adults, itchy skin can sometimes be the sign of a serious medical problem. Such problems can include:

• kidney failure
• liver disease
• a blood disorder

Itchy skin can also be due to:

• an overactive thyroid or under active thyroid
• HIV infection
• advanced cancer
• illnesses that affect your nervous system
• a mental health illness

When should I see my doctor?

See your doctor if:

• you are very itchy and there is no rash
• if you are concerned about a rash that is not going away

It’s very important to let them know about the any medicines you are taking. These include over-the-counter medicines and herbal medicines.

See you doctor if:

• you are unwell or have a fever
• the symptoms keep coming back
• the itching is so bad you cannot sleep
• the rash is bleeding, scabs or has pus
• you develop severe itching while you are pregnant

It is always a good idea to see a doctor if your baby develops a rash.

How is itchy skin diagnosed?

The treatment of itchy skin depends on what is causing it. Most causes of itchy skin can be diagnosed by examination (looking at you) and don’t need special tests.

Your doctor may arrange for:

• a skin biopsy
• blood tests
• urine (wee) tests
• stool (poo) tests

How is itchy skin treated?

If you have itchy skin, here are some things that may help:

• Try not to scratch the area. The more you scratch, the more your skin will itch.
• Keep your nails short to prevent breaking your skin if you do scratch.
• Try to wear loose cotton clothing. This can help prevent you overheating and making the itch worse. Avoid fabrics like wool which can irritate your skin.
• Reducing stress. Some ways to help reduce stress are meditation, yoga, and exercise.

In the bathroom

• A cool bath or shower may help provide short-term relief form the itch. Remember that a lot of showering or bathing can also make it worse.
• Do not use any soaps, shower gels or foam bath products. These can dry your skin and make the itching worse. Use a soap-free wash.
• After a bath or shower gently pat yourself dry with a clean towel. Do not rub or use the towel to scratch yourself.
• Use moisturiser all over your skin at least 2 times a day. Use it more often if your skin feels dry. You can buy cooling moisturisers that contain menthol. This can soothe the itch.

Your pharmacist may be able to recommend some products which can help with itchy skin.

How can itchy skin be prevented?

Drink lots of water to keep well hydrated. Using a humidifier in dry weather can help.

Make sure you have quick showers and don’t have the water too hot.

Choose a mild soap or a non-soap cleanser. Use moisturiser after a shower or bath, while your skin is still damp.

Complications of itchy skin

It’s very hard to stop scratching an itch. Sometimes after you have scratched an itch it seems to become even itchier. You can get into a cycle of itching and scratching. This can be painful. Sometimes it can lead to an infection if the skin is broken.

The scratching can also lead to brown or pale marks on the skin or lumps. It can also cause bruising or scarring.