Your patient is to receive Acyclovir 5 mg/kg IV. You have available a 500 mg vial. The patient weighs 132 lbs. The package directions tell you to inject 8 mL into the vial. How many mL will you withdraw from the vial? (Round to the nearest tenth). ____ mL

Step 1: Convert weight from pounds to kilograms 132 lb ÷ 2.2 = 60 kg Step 2: Calculate the ordered dose Dose = 5 mg/kg 5 mg × 60 kg = 300 mg Step 3: Determine concentration after reconstitution The vial contains 500 mg and is mixed with 8 mL. Concentration = 500 mg ÷ 8 mL = 62.5 mg/mL Step 4: Find how many mL to withdraw mL to give = Dose ordered ÷ Concentration 300 mg ÷ 62.5 mg/mL = 4.8 mL Correct Answer: 4.8 mL