Lactose Intolerance in babies – Our Story

This is not the most glamorous of posts, but its something I hope will help other parents who find themselves in the position I was in a couple of weeks ago with my 10-month-old son Reuben. Dealing with severe diarrhoea in babies can be tricky especially when there is no specific cause. Here is our story and how I came to find out the sudden onset of diarrhoea was actually due to him developing an intolerance to lactose in dairy products.

Rueben’s diarrhoea episode came on suddenly and out of nowhere. He hadn’t eaten anything new, didn’t have any allergies and wasn’t sick or have a temperature. He was eating and drinking normally, but after a couple of days, I wanted to get him checked out by our GP.  After numerous trips to the doctors and many tests for bugs or parasites, the doctors were at a loss for what was causing the diarrhoea. All the tests came back negative. I was told merely to give it time and eventually his body would get over whatever was causing the diarrhoea.

The only advice I had from the doctors I saw was to increase Reubens intake of bananas, bread and rice – in line with the BRAT diet which is used to treat adults with diarrhoea.

This was not the news I wanted to hear. Any mum knows that looking after a baby with diarrhoea is no fun for mum or baby. While he was happy in himself, he was suffering from a severe nappy rash which no matter what cream I used didn’t seem to be improving.

After 10 days of Reuben suffering from the diarrhoea and still no improvement after increasing his intake of bananas, bread and rice, it suddenly dawned on me that the only thing that hadn’t changed was his milk.

I instantly went to Google and started researching milk allergies. After ruling this out – no wheezing, rashes, hives, running nose etc. I then looked at food intolerances and then came across lactose intolerance.

Everything suddenly made sense. Babies can develop either temporary or permanent lactose intolerances especially after being on antibiotics. It’s thought that the antibiotics while treating the infection also kill off the “good” bacteria in the gut. This “good” bacteria is often used to break down the lactose in milk. Reuben had recently been treated for a chest infection, so it’s possible that his body had no  “good” bacteria left to break down the enzymes in the lactose causing the diarrhoea.

That morning I went and bought lactose-free milk, and within hours things were returning to normal. After 48 hours everything was pretty much back to as it was before Reuben became poorly including the nappy rash. The interesting thing about diarrhoea caused by lactose intolerance is that the urine and faeces produced are often more acidic than normal which causes the severe nappy rash.

Reuben is now on lactose-free milk and dairy products and is as happy as ever. I have found it easy to change to lactose-free products and the whole family eat/drink them without noticing that anything has changed. In the future, we will test to see if Reuben remains lactose intolerant or whether his body has been able to increase his level of “good” gut bacteria on its own. In the meantime, we are using a supplement called OptiBac Probiotics For babies & children – Pack of 30 Sachets available from Amazon* which has made a massive improvement to Reuben’s digestion (please consult your doctor before trying any new supplements for babies and children).

If you have a baby that develops sudden diarrhoea and after tests, there seem to be no reasons as to why they have developed it, I would suggest looking into allergies or intolerances into the milk as a possible cause.

Please feel free to share your experience with other mums and me down below and please feel free to leave any questions or comments for me.


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