A nurse is preparing to administer nystatin 400,000 units PO every 6 hr. Available is nystatin oral suspension 100,000 units/mL. How many mL should the nurse administer per dose? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)

Determine the total daily dosage: The client is prescribed 400,000 units of nystatin every 6 hours. There are 24 hours in a day, so the medication is given 24/6 = 4 times a day. Total daily dosage is 400,000 units/dose x 4 doses = 1,600,000 units per day. Calculate the dosage per dose: The medication is to be administered in divided doses every 6 hours. There are 24 hours in a day, so the medication is given 24/6 = 4 times a day. Dosage per dose is 1,600,000 units / 4 doses = 400,000 units per dose. Determine the number of mL per dose: The nystatin oral suspension contains 100,000 units per mL. The nurse needs to administer 400,000 units per dose. Divide 400,000 units / 100,000 units per mL = 4 mL per dose.