Question

A 38-lb child is prescribed acyclovir for chicken pox in an amount of 80 mg/ kg body weight per day to be divided in four doses each tablet contains 700 mg of the medicine. How many tablets should be given per day? Per dose

Answer 1

Answer:

$\large \boxed{\text{Two tablets per day; half a tablet per dose}}$

Explanation:

1. Convert pounds to kilograms

$\text{Body weight} = \text{38 lb} \times \dfrac{\text{1 kg}}{\text{2.205 kg}} = \text{17.2 kg}$

2. Convert kilograms of body weight to milligrams of acyclovir

$\text{Mass of acyclovir} = \text{17.2 kg} \times \dfrac{\text{80 mg acyclovir}}{\text{1 kg}} = \text{1380 mg acyclovir }$

3. Convert milligrams of acyclovir to number of tablets

$\text{No. of tablets} = \text{1380 mg} \times \dfrac{\text{1 tablet}}{\text{700 mg}} = \textbf{2 tablets}$

4. Calculate the tablets per dose

The child must receive two tablets in four doses.

$\text{Tablets per dose} = \dfrac{\text{2 tablets}}{\text{4 doses}} = \textbf{0.5 tablets per dose}\\\\\text{The child must receive \large \boxed{\textbf{two tablets per day and half a tablet per dose}} }$