Question 987009
The dosage is 600 mg a day, since it is given every 6 hours.
The weight of the child is 13.64 kg
600 mg/day/13.64 kg is the right units and it is 44.  That is too high by 10%.  I would give 135 mg every six hours, 10% less.  The total daily dose would be 540 mg, which is 39.60 mg/kg/day. Alternatively, one could give 150 mg three times a day, or 450 mg/day.  That would be 33 mg/kg/day, which would also be suitable.
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Each dose should be between 0.5 and 1 mg/kg
15 ml of Tylenol #3 contains 36 mg of codeine, since it is three times 5 ml.
That is 2.64 mg/kg, which is too much by a factor of 2.5 to 5.
The child should get about 20-40% of that amount prescribed or about 5 ml, not 15 ml. That would be 12 mg of codeine per dose, and that would be 0.88 mg/kg/dose.