A nurse is preparing to administer cetirizine 5 mg PO. Available is cetirizine 2.5 mg/5 mL. How many mL should the nurse administer? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)

Calculation: Desired dose = 5 mg. Available concentration = 2.5 mg / 5 mL. Calculate the required volume using the formula: Volume (mL) = Desired dose (mg) / Available concentration (mg/mL) = 5 mg / (2.5 mg / 5 mL) = 5 mg × (5 mL / 2.5 mg) = (5 × 5) / 2.5 mL = 25 / 2.5 mL = 10 mL Rounded to the nearest whole number: 10.