What is youngs rule formula? From where can we get 12 in these formula

Young's rule is a formula used in pediatrics to calculate the appropriate pediatric dose of a medication based on the age of a child. The formula is:

Child's dose = (Age in years / (Age in years + 12)) * Adult dose

The number 12 in the formula represents the age at which a child is considered to have reached adulthood. This is a general approximation and may vary depending on the specific medication and medical guidelines being followed. It is important to note that Young's rule is an estimation and should be used with caution. It is always advisable to consult a healthcare professional for accurate dosing information for children.