NEW YORK (Reuters Health) - The use of commonly prescribed "broad-spectrum" antibiotics, which destroy a wide range of bacteria, during infancy may raise the risk of asthma later in childhood, according to a Canadian report in the journal Chest.

"Antibiotics are prescribed mostly for respiratory tract infections, yet respiratory symptoms can be a sign of future asthma. This may make it difficult to attribute antibiotic use to asthma development," lead author Dr. Anita Kozyrskyj said in a statement. "Our study reported on antibiotic use in children being treated for nonrespiratory tract infections, which distinguishes the effect of the antibiotic," she explained.

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