Questions: A nurse is preparing to administer ibuprofen 10 mg / kg PO every 6 to 8 hr PRN pain to a child who weighs 55 lb. Available is ibuprofen suspension 100 mg / 5 mL. How many mL should the nurse administer per dose? (Round the answer to the nearest tenth. Use a leading zero if it applies. Do not use a trailing zero.)

Solution Steps

To solve this problem, we need to first convert the child's weight from pounds to kilograms. Then, calculate the required dose in milligrams using the dosage guideline of 10 mg/kg. Finally, convert the dose from milligrams to milliliters using the concentration of the ibuprofen suspension.

To convert the child's weight from pounds to kilograms, we use the conversion factor \( 1 \, \text{lb} = 0.453592 \, \text{kg} \): \[ \text{weight}_{\text{kg}} = 55 \, \text{lb} \times 0.453592 \, \text{kg/lb} \approx 24.9476 \, \text{kg} \]

Using the dosage guideline of \( 10 \, \text{mg/kg} \), we calculate the required dose: \[ \text{required dose}_{\text{mg}} = \text{weight}_{\text{kg}} \times 10 \, \text{mg/kg} \approx 24.9476 \, \text{kg} \times 10 \, \text{mg/kg} \approx 249.476 \, \text{mg} \]

The concentration of the ibuprofen suspension is \( 100 \, \text{mg} / 5 \, \text{mL} = 20 \, \text{mg/mL} \). To find the volume in milliliters: \[ \text{required dose}_{\text{mL}} = \frac{\text{required dose}_{\text{mg}}}{\text{suspension}_{\text{mg/mL}}} = \frac{249.476 \, \text{mg}}{20 \, \text{mg/mL}} \approx 12.4738 \, \text{mL} \] Rounding to the nearest tenth gives: \[ \text{required dose}_{\text{mL}} \approx 12.5 \, \text{mL} \]

Final Answer