The details in this section are for general information only. Always check with your own doctor.
If your child has rhino-sinusitis (a persistent runny nose), you might have wondered if an allergy to milk or dairy products is responsible as this is often mentioned in the media and on some websites. Some people think that milk causes excess mucus, and that this in turn causes rhino-sinusitis. This may be because of the sensation of coating the throat experienced when drinking milk, but this occurs similarly with other viscous fluids and does not mean that more mucus is produced.
There is no proven relationship between drinking milk and excess mucus.
Milk allergy does affect around 5% of infants but when it does occur, the symptoms are more marked than those in the nose, and it does not cause nasal symptoms in isolation.
Milk allergy is most commonly indicated by gut symptoms (colic or diarrhoea) and by failure to thrive (lack of weight gain). Other symptoms could include vomiting, rashes (eczema or hives), runny or blocked nose, bronchitis or wheezing, cough, irritability, and acute middle ear infections or glue ear. Just a runny or blocked nose is very unlikely to be a sign of an allergy.
The onset of a milk allergy tends to start in early infancy (in the first few months). The reaction is immediate. It is caused by a reaction of substances in the milk (alpha-lactalbumin and beta lactoglobulin) with a substance in the blood called immunoglobulin E (IgE). You might find your baby can tolerate sterilised milk as the substances responsible evaporate at high temperatures. If allergy is suspected a skin prick test or blood test can help to detect it.
Some children who do not have an allergy can have an intolerance to milk. This is different to an allergy. The symptoms include diarrhoea and vomiting, and possibly skin or respiratory problems. The onset is likely to be some hours or even days after taking the milk. You can determine whether someone has an intolerance by eliminating the suspected food, and then gradually reintroducing it, while monitoring symptoms.
Milk proteins may be found in milk, buttermilk, whey, curds, lactose, casein, caseinate, margarine, cream, cheese, butter, yoghurt, lactalbumin, lactoglobulin.
If your child has a food allergy or intolerance and you need to eliminate certain foods from their diet please seek the advice of a dietician. 50% of young children with an allergy to milk have other food allergies as well, so it is essential to get professional help with devising a suitable diet.
If your child has rhino-sinusitis it is far more likely that there are other reasons for it. Click here to read more information about the causes and treatment of rhino-sinusitis