A nurse is preparing to administer amoxicillin 320 mg PO every 12 hr to an infant. The amount available is amoxicillin suspension 400 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.) . . .

Step 1 is to use the concentration available to calculate the volume (mL) needed to administer the ordered dose (mg). Volume (mL) = Dose ordered (mg) ÷ Concentration available (mg/mL). Step 2 is to first determine the concentration available in mg/mL. 400 mg ÷ 5 mL = 80 mg/mL. Step 3 is to calculate the volume to administer per dose. 320 mg ÷ 80 mg/mL = 4 mL. The nurse should administer 4.0 mL per dose. .