A nurse is preparing to administer haloperidol lactate 7 mg PO to a client who has psychosis. Available is haloperidol lactate 2 mg/mL oral solution. How many mL should the nurse plan to administer? (Round to the nearest tenth. Use a leading zero if it applies.

Answer and explanation Step 1 is to calculate the volume of haloperidol lactate oral solution that contains 7 mg of haloperidol lactate. This is done by dividing the prescribed dose (7 mg) by the concentration of the oral solution (2 mg/mL). So, 7 mg ÷ 2 mg/mL = 3.5 mL. So, the correct answer is 3.5 mL.