Intolerances are a reflection that there is a problem or imbalance with the gut, intolerances are considered to be different to allergies and as such can be affected by repairing and treating the digestive system.
Given the history of reflux and a family history of similar type reactions to lactose I believe that your son’s reaction is most likely an intolerance caused by a gut imbalance. It is not uncommon for children to grow out of these intolerances as they age and their digestive system and immune systems gain exposure to a wider range of foods. It is of course necessary to treat this intolerance as serious in one so young. I have given advice that is general for your son’s condition with the suggestion that you visit a Naturopath. I am able to offer the names of several exceptional Naturopaths in Queensland if you require one. Visiting a Naturopath would allow you to receive a tailored digestive repair protocol that would allow your son the best possible chance to grow and recover from his intolerances quickly.
If dairy products are a problem it is usually because of two main culprits: lactose and casein. Lactose free milk does not necessarily mean that the casein has been removed and as such if your son is ready to be weaned off Formula the introduction of a dairy free milk may be a suitable option. If your other son reacted favourably to soy this may be a good place to start, alternatively almond or rice milk may be suitable options. Due to your son reacting to yoghurt (which is considered to have a lower lactose profile) I would consider that his intolerance is not only a lactose based one.
A history of reflux from birth can indicate several conditions. Infant reflux is often because the pyloric sphincter which is on top of the stomach is not developed properly and this causes a reflux. Treatment for this condition is often medication or the use of reflux formulas which make the milk thicker and harder to vomit up. As the child develops the condition improves. The other cause of infant reflux is general digestive function. In an infant several factors may predispose them to a digestive system that is not quite optimal. These include:
Caesarean birth : vaginal delivery is considered to provide the digestive system with the necessary digestive flora for a functional immune and digestive system. If your son was delivered via caesarean it is important to provide his digestive system with the beneficial bacteria. In your son’s case you will need to source a dairy free probiotic. These are available in the Natren, Bioceuticals and Inner Health ranges.
Family History of allergy or intolerance: We pass onto our children many of their most endearing traits as well as their health. If there is a family history of asthma, allergies, intolerances and digestive problems these will often be reproduced in our children. Being aware of your own health and the health of your other children will often give you an insight into the health of your son.
Unfortunately stories like that of your son are increasingly common. The promising factor is that your two other children grew out of their intolerances and reflux. I suggest that the introduction of a probiotic is essential as is the use of healing and soothing plant fibres such as slippery elm. Slippery elm will aid in reducing the reflux as well as providing a vehicle of transport for the beneficial bacteria to travel through the colon. Slippery elm is regarded as a non reactive plant fibre that heals and soothes the digestive tract. In your son’s case I would introduce it at the end of a meal. It can be mixed with juice or fruit. It is considered that it forms a "boat" over the contents of the stomach minimising reflux. Paying close attention to his reactions to other foods in his diet may also identify any other triggers.