Dosages vary among protocols, but most are based on your child’s weight or body surface area (BSA). BSA is calculated from your child’s weight and height and is measured in meters squared (m²). Doses of medications your child is scheduled to receive should be recalculated by the doctor at the beginning of each new phase of treatment. Recalculating doses more frequently is necessary if your child experiences significant weight gain or loss (more than 10 percent of his initial weight).

You do not need to do the calculations, but it is important to know the appropriate dosage for each drug and how you should give it to your child. Most families write the dosages for each drug on a calendar and cross them out after each dose has been given to make sure they don’t forget a drug or accidentally repeat a dose.