A nurse is preparing to administer erythromycin ethylsuccinate 800 mg PO every 4 hr. Available is erythromycin ethylsuccinate 200 mg/5mL. 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.)

To administer the correct dose of erythromycin ethylsuccinate, which is 800 mg, when the available medication concentration is 200 mg per 5 mL, the nurse needs to calculate the volume of medication to provide the prescribed dose. The calculation is as follows: 800 mg divided by 200 mg equals 4. Then, multiply 4 by 5 mL to get the total volume needed for the 800 mg dose. Therefore, the nurse should administer 20 mL of erythromycin ethylsuccinate to deliver the prescribed 800 mg dose.