What's making you itch: From penicillin to perfume or the menopause – the causes of that maddening tingle
22:35 GMT, 3 September 2012
The sensation of itchy skin drives many of us potty every day.
The medical name for it is pruritus, and it is defined as itching caused by the stimulation of nerve endings in the skin.
Here, ANGELA EPSTEIN speaks to the experts to reveal the triggers behind the urge to scratch.
The medical name for itchy skin is pruritus, and it is defined as itching caused by the stimulation of nerve endings in the skin
AS IF ANTS ARE CRAWLING ON YOU
PROBABLE CAUSE: Menopause. Changes in hormone levels can produce an itchy skin condition called formication.
Sufferers have the phantom sensation of insects crawling on their skin, though it’s not clear why. One theory is that fluctuating hormone levels may affect nerve endings in the skin.
TREATMENT: Increasing your intake of omega-3 fatty acids (found in oily fish) can help improve skin condition, and if the skin is less dry it may be less prone to itching, says Dr Tabi Leslie, a dermatologist at St Thomas’ and Barnet hospitals in London.
Drinking plenty of water to keep the skin hydrated may help reduce irritation, as can avoiding smoking, excess sun exposure, stress and lack of sleep.
Hormone replacement therapy may also help. The condition should settle after the menopause, says Peter Bowen Simpkins, medical director of the London Women’s Clinic.
FIERY ITCH AND RED, WEEPY SKIN
PROBABLE CAUSE: Allergy. Often referred to as allergic contact dermatitis, this occurs when the skin reacts to something touching it.
Common triggers include nickel jewellery, rubber gloves or a buckle from a belt.
It can also be caused by irritants such as chemicals in soaps or perfumes.
Allergens produce an immune response in the skin, which triggers the fiery itch.
In severe cases the skin can become scaly with painful cracks developing on the fingers, says Dr Andrew Wright, a dermatologist at Bradford Hospitals NHS Trust.
People with a tendency to asthma, eczema and hay fever develop contact dermatitis more easily than others, possibly due to a compromised immune system, and this tendency can run in families.
TREATMENT: The first step is to identify the cause, says Dr Wright, so monitor what you use when you get an outbreak. Patch testing may help.
Here, small pieces of sticky tape — each containing a small sample of a potentially allergic substance — are applied to the skin for 48 hours and any reaction is then analysed.
Moisturise regularly as this helps maintain the skin’s protective barrier and use hypoallergenic shampoo and soap because this is free from common allergens.
PRICKLY, INTENSE ITCHINESS
Other symptoms: Sudden rash or mild red patches.
PROBABLE CAUSE: Eczema. One in five people will be affected by eczema (also known as dermatitis) at some time in their lives.
The condition is caused by an over-reaction of the immune system. Atopic eczema tends to be hereditary and many sufferers will also have hay fever and asthma, conditions linked to a compromised or overactive immune system function.
Prime sites are behind the knees, elbows, side of neck or around the eyes and ears as these areas become hot and clammy.
Pompholyx eczema affects one in 20 people, and produces a burning itching along with tiny blisters on the sides of the fingers, palms and feet.
The cause isn’t known, but it can be triggered by perfume, athlete’s foot or stress.
TREATMENT: Keep the skin well moisturised because dry skin is more easily irritated, says Dr Leslie. Use creams free from chemicals such as parabens. Hydrocortisone can also be soothing.
A new treatment, Tacrolimus ointment, is available on prescription for those with moderate to severe eczema, and helps calm an overactive immune system.
An oatmeal bath can help, too, says GP Dr Paul Griffiths of the Blemish Clinic in Manchester. Oats contain anti-inflammatory compounds that can reduce itching.
ITCHY RED-BROWN RASH
PROBABLE CAUSE: Medication. Some drugs, such as penicillin and other antibiotics, can cause itchy skin, says Dr Wright.
This is because the drugs are treated as a foreign chemical in the body and produce an allergic reaction within hours.
TREATMENT: Speak to your doctor about changing your medication.
‘Desensitisation’ can be used for penicillin allergy if the drug has to be taken regularly.
BURNING RASH FROM BEING IN THE SUN
Other symptoms: Small red spots or blisters.
PROBABLE CAUSE: Sun allergy. As little as 15 minutes in the sun can trigger polymorphic light eruption, an immune reaction that causes a burning itchy rash on the chest and arms.
This occurs about a day after the first exposure and produces small red spots or blisters. It affects around one in ten people, and is more common in women than men.
TREATMENT: Calamine lotion, or corticosteroid cream and antihistamine tablets, can help. To prevent it, try exposing yourself to sunlight gradually.
GENERAL ITCHING AND HOT, PAINFUL SKIN
Dry skin often feels itchy as it is more easily irritated
PROBABLE CAUSE: Urticaria. Also known as hives, this condition occurs when too much histamine — a chemical produced in response to an allergen — is released by the cells in your skin.
This produces white or red welts (a swollen mark about 1cm in size), which can sometimes itch.
There are two types: acute and chronic. Acute urticaria occurs after a cold or flu, an insect sting or contact with chemicals in food such as tomatoes, tuna, straw-berries and bananas.
Chronic urticaria lasts more than six weeks, and occurs when antibodies from your immune system attack the body, causing the release of histamine.
Alcohol, stress and high blood pressure tablets can make the condition worse.
TREATMENT: Over-the-counter antihistamines can help. But avoid non-steroidal anti-inflammatory drugs, such as aspirin and ibuprofen, as these can also produce an allergic reaction that would exacerbate the condition.
MILD, CONSTANT ITCH AND RED PATCHES
Other symptoms: Silvery white scales.
PROBABLE CAUSE: Psoriasis. Around one in 50 people have this condition, where the skin grows about seven times more quickly and thickly than usual.
Psoriasis often affects the elbows, knees, lower back and scalp and usually strikes between the ages of 15 and 30, or after 40.
It is thought to be linked to an abnormal immune reaction, but it can be triggered by stress and hormonal changes.
TREATMENT: Sun exposure can help as it boosts levels of vitamin D, which is thought to dampen skin growth.
Vitamin D is also available as an ointment.
Bathing in warm water with a bath oil or tar solution can soften psoriasis and lift the scale, says Dr Sandeep Cliff, a dermatologist at East Surrey Hospital. He also advises cod liver oil as the omega-3 fats help reduce inflammation.
PROBABLE CAUSE: Dry skin. Xerosis, the medical name for it, often feels itchy as it is more easily irritated. Skin dries out with age, though itchiness can be exacerbated by factors such as air conditioning and swimming in chlorinated water.
Those with an underactive thyroid may also suffer.
TREATMENT: As well as using plenty of moisturiser, avoid getting too much shampoo on the skin as it contains detergents that strip moisture and increase dryness.