Warning: People with eczema who use aqueous cream could be making their condition worse.
Many family doctors are routinely prescribing a treatment for the skin condition eczema that can make the symptoms worse, according to a new survey.
Around 90 per cent of GPs say they prescribe aqueous cream to patients, yet a staggering 85 per cent are giving it to patients incorrectly.
They are prescribing it as a moisturiser to help combat the dry skin associated with conditions such as eczema.
However, it was actually developed as an alternative to soap - and only a small proportion of GPs prescribe it for this.
'If people with eczema leave aqueous cream on their skin, it could make their condition worse,' explains Dr Tony Bewley, who is a consultant dermatologist at Whipps Cross and Barts Hospital in London.
'People with eczema do not produce as much natural oil in their skin, so it tends to become dry. This means it has to be kept moisturised or it will become overdry and crack.
'However, aqueous cream will not really help - not least because it does not contain much actual moisturiser.
'In fact, aqueous cream contains a detergent - although not as much as conventional soap - which is why it's good as an alternative to shower gels or soap if you have dry skin or eczema.
'But this makes the cream alkaline - and because the skin is naturally slightly acidic, this breaks down its natural barrier.
On top of that, some aqueous creams contain sodium lauryl sulphate, a detergent that further breaks down the skin barrier, which makes the skin more sensitive and the eczema worse.
'So people who are applying it and leaving it on in the hope that it will soothe their dry patches, may find that the skin becomes cracked and raw instead.'
Indeed, many children refer to aqueous cream as 'the stinging cream' because it irritates their skin so much, reports the National Eczema Society.
One study found that 56 per cent of children had an irritant reaction to aqueous cream compared with 17 per cent of children using all emollients (medical moisturisers).
'We get calls from mums saying their child won't let them apply their emollient because it stings, or that the one they are using isn't working - and invariably it turns out that they are using aqueous cream,' says Margaret Cox, chief executive of the National Eczema Society.
'Adults also suffer, but what tends to happen is that their GP gives them the cream, they use it for a bit, find it makes no difference and then stop using it.
'They then don't bother going back to get anything else because they presume nothing more can be done.' Dr Bewley says he has people being referred to his dermatology clinic whose condition has been made worse through the prescription of inappropriate treatments such as aqueous cream.
'Children and the elderly have thin and sensitive skin anyway, so they are more prone to get a reaction,' he says.
'However, I see people of all ages whose eczema has got out of hand because they've been using aqueous creams rather than rich emollients.
'It's not really the GPs' fault. They are given only a couple of weeks' training in skin at medical school, even though skin complaints account for about 20 per cent of all GP consultations.
'GPs are also under pressure to keep their budgets in good order, and aqueous cream is cheap.'
Dr Bewley says people should stick to medical moisturisers such as white soft paraffin, liquid paraffin 50 50, or emulsifying ointments, and experiment until they find one that works for them.
'Everyone is different and finding the right cream is a question of trial and error. Also, needs vary from season to season. People may find that they need a richer cream in the winter, as the skin dries out and produces less oils in the cold weather. And just use aqueous cream to wash in.'
Margaret Cox urges people to ask their GPs for an alternative if they are given aqueous cream. They can also check the society's website or call the helpline for suggestions of alternatives.
Some aqueous creams are less likely to irritate because they don't contain the detergent sodium lauryl, which can further upset sensitive skin.
These include Doublebase, EpiDerm, Dermamist, Hydromol, Dexeryl and Emollin.