A new report claims babies who are given antibiotics before they are six months old are at a higher risk of developing asthma.
Researchers at America's Yale University say that early exposure to antibiotics is risky, even if the child is not genetically predisposed to asthma. They claim the drugs affect the balance of microbes in the body which would normally defend against illness.
The risk is raised by 40, the research says.
Antibiotics have been linked to asthma in the past, but medics have always disagreed as to whether the affected children would have gone on to develop the condition anyway.
Dr Kari Risnes who led the research said: 'Our study should encourage doctors to avoid unnecessary antibiotic use, especially in low-risk children.'
Around 1.1 million children in the UK have asthma. Previously, links have been made with excessive paracetamol consumption
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