Children who are given antibiotics in their first three months often wheeze by the time they are 15-months-old, but it is probably not because of the antibiotics, a new study has found.
The Otago University study found the wheezing was probably due to chest infections rather than the use of antibiotics.
Wellington Asthma Research Group director Professor Julian Crane said the study followed about 1000 children, in Wellington and Christchurch, from birth to four-years-old.
It showed by the time the children had reached 15 months 72.1 percent had been given antibiotics, 11.8 percent had asthma, 39.6 percent had eczema and 21.2 percent had a recurring itchy scaly rash.
"Our results strongly suggest that the reason that some children who've been given antibiotics appear to develop asthma is because they had a chest infection and the symptoms of the chest infection in young children can be confused with the start of asthma," Prof Crane said.
"Antibiotics are then given to treat this respiratory condition, which may or may not be asthma, and are not a cause as has been previously suggested."
He said the study "leaves open the possibility" that antibiotics had something to do with the development of eczema and itchy skin by four years, and allergic hypersensitivity by 15 months.
Prof Crane said there was a theory that asthma had increased in line with antibiotic use over the last 40 years.
"The study concludes, however, that much of the effect of antibiotics on the development of asthma in infancy can be explained by chest infections which are often difficult to distinguish from asthma at an early age."
The study was funded by the Health Research Council, the Child Health Research Foundation and the David and Cassie Anderson Bequest.
NZPA