Cow's milk allergy in babies is being missed by doctors, a survey suggests.
Special formula may be prescribed
Nearly 80% of 500 doctors polled by a formula milk manufacturer thought their colleagues confused milk allergy symptoms with other conditions.
Experts say the problem lies in the symptoms being both vague and common - including skin rashes and diarrhoea.
The poll also found many of the doctors did not know the best treatment. Without treatment food allergies can be distressing and even deadly.
Officials recommend babies who are allergic to cow's milk can be given special low-allergy or hypoallergenic milk, such as an amino-acid based formula.
Many of the doctors questioned, however, said they would advise a soy-based formula.
The Department of Health and the British Dietetics Association advise against this because soy contains high levels of compounds called phytoestrogens that mimic the action of the female hormone oestrogen and which could pose a risk to the long-term fertility of infants.
There is also a risk that babies who are allergic to cow's milk will also be allergic to soy milk, and sheep and goat's milk.
Cow's milk protein allergy
Symptoms can be vague and include diarrhoea, vomiting, wheezing and skin rashes
Not to be confused with food intolerances, such as lactose intolerance, which do not involve the immune system
Other common food allergies in infants are soy, egg, peanuts, wheat and shellfish
Correct advice is to avoid cow's milk and seek medical advice, which may include using a prescribed hypoallergenic formula milk
According to the Food Standards Agency, allergy to cows┐ milk is the most common food allergy in childhood and affects 2-7% of babies under one year old.
Nearly all of the doctors questioned agreed that better information would make it much easier to diagnose the condition in infants.
The taskforce, which includes expert paediatric gastroenterologists, has developed guidance for doctors that will be published next year.
Judith Moore, paediatric dietician and spokeswoman for the British Dietetics Association, said: "If a parent suspects their baby has a milk allergy then they should see their GP who can refer them to a paediatric dietician.
"If you take a good medical history then you can pick it up but it can be difficult to diagnose. The symptoms do vary so it can be hard to spot."
She added that many babies whose parents suspect have an allergy turn out not to have one.
Left untreated, infants with food allergies can fail to thrive and grow, have developmental problems and can develop severe shock and even die.
The World Health Organization recommends that babies are breastfed for the first two years of their lives if possible.
The poll was carried out by Act Against Allergy, an initiative set up to increase awareness of milk allergy, by SHS International Ltd, which produces its own versions of formula milk.