Question

the hcp has ordered chlorothiazide 400 mg po q12h for your patient to treat her congestive heart failure. the child weighs 121.4 lb. the recommended dosage: chlorothiazide 10 mg to 20 mg/kg/day po q12h what is the safe daily dose range for this child?

Explanation:

Step1: Convert weight from lb to kg

Since \(1\ lb = 0.4536\ kg\), the weight of the child \(m = 121.4\times0.4536\ kg\approx55\ kg\)

Step2: Calculate the lower - bound of the daily dose

Using the formula \(D_{min}=10\ mg/kg/day\times m\). Substitute \(m = 55\ kg\), we get \(D_{min}=10\times55\ mg = 550\ mg/day\)

Step3: Calculate the upper - bound of the daily dose

Using the formula \(D_{max}=20\ mg/kg/day\times m\). Substitute \(m = 55\ kg\), we get \(D_{max}=20\times55\ mg=1100\ mg/day\)

Answer:

The safe daily dose range for this child is \(550\ mg/day\) to \(1100\ mg/day\)