The maximum daily dose of Flucloxacillin in paediatrics is 25mg/kg; if yours is a normal 2 year old, a total daily dose of 250-300mg is the maximum treatment recommendation. I understand she ingested a dose twice that of the maximum level. Flucloxacillin has more toxic effects on the liver, it also has some side effects on the kidney. To be sure, go to an emergency room or visit the paediatrician as soon as possible and request for blood tests or urine tests. He may need to be examined and observed there too. I do hope this helps.
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