Is my eight-month-old child allergic to milk?

Vomiting is one way (apart from diarrhoea), the body expels from the alimentary canal what is eaten or drunk but deemed to have a potential of harming one’s health.

Children below one year may have a milk allergy (to Casein and Whey Proteins) so that even when milk is taken in small quantities disguised in porridge,  the body may react, leading to vomiting and other symptoms like a skin rash, runny nose, cough or diarrhoea.

That said, infants may fail to properly digest a sugar in milk called lactose , ending up with the same symptoms as the milk allergy.  Here though, vomiting is less common and the intolerance worsens when bigger amounts of milk are consumed.

 Whereas allergy to milk may start in infancy,  lactose intolerance usually starts later in childhood and worsens with age, becoming worst in adulthood. Also, the intolerance does not lead to an itchy skin rash, cough or runny/stuffy nose symptom of a milk allergy unless one coincidentally has an allergy and intolerance at the same time.

Skin allergy tests may be done to differentiate milk allergy from lactose intolerance because the two have different ways of management.

After giving milk and doing a hydrogen breath test, an increase in hydrogen can indicate lactose intolerance.

Fortunately, by three years many children may have outgrown an allergy to milk which is too nutritious to avoid taking. Also, the allergy is usually to animal milk or formula but rarely to breast milk so that breastfeeding without supplementation with milk products is key to treatment. 

Some people with allergy to milk may also be allergic to soy milk, requiring in the circumstances that they avoid it as well.

Lactose intolerance is usually not very serious requiring use of lactase enzyme supplementation and diluting the milk or milk products. 

When the intolerance is serious one may need to discontinue milk altogether and supplementing with non-milk substitutes say containing calcium.