Questions: A nurse is preparing to administer phenytoin 300 mg PO daily. Available is phenytoin oral suspension 125 mg / 5 mL. How many mL should the nurse administer? (Round the answer to the nearest whole number.)

Solution Steps

To determine how many mL of phenytoin oral suspension the nurse should administer, we need to set up a proportion based on the concentration provided. The concentration is given as 125 mg per 5 mL. We need to find out how many mL correspond to 300 mg. By setting up a proportion and solving for the unknown volume in mL, we can find the answer.

The concentration of the phenytoin oral suspension is given as \(125 \, \text{mg} / 5 \, \text{mL}\). To find the concentration in mg/mL, we divide the amount of drug by the volume:

\[ \text{Concentration} = \frac{125 \, \text{mg}}{5 \, \text{mL}} = 25 \, \text{mg/mL} \]

The nurse needs to administer a dose of \(300 \, \text{mg}\). Using the concentration calculated in Step 1, we can find the volume in mL required to deliver this dose:

\[ \text{Volume} = \frac{300 \, \text{mg}}{25 \, \text{mg/mL}} = 12 \, \text{mL} \]

Since the problem asks for the volume to be rounded to the nearest whole number, we round \(12 \, \text{mL}\) to:

\[ \boxed{12 \, \text{mL}} \]

Final Answer