Avoiding complications from spreading bacteria is one of the most important reasons to treat ear infections with antibiotics. Mastoiditis, an infection of the skull bone behind the ear, is the most common serious complication. A major study published in the August 2001 issue of the Pediatric Infectious Disease Journal compared children in the US, UK, Canada, and Australia (where more than 96% of acute ear infections in children are treated with antibiotics) with children in the Netherlands, Denmark, and Norway (where only 31% to 76% of acute ear infections are treated with antibiotics). Complications are indeed more common when people 'watch and wait' before treating many ear infections -- but the increased complications only totaled 2 extra cases of mastoiditis per 100,000 children per year. Adverse reactions to antibiotics can be a bigger problem than spreading ear infections. Clearly some ear infections are best treated with antibiotics, but I favor watching and waiting (with good pain treatment for the child) whenever it makes clinical sense. I hope the days of knee-jerk antibiotic treatment for ear infections are coming to an end.