A nurse is preparing to administer valproic acid 125 mg PO. Available is valproic acid syrup 250 mg/5 mL. How many mL should the nurse administer? (Round the answer to the nearest tenth. Use a leading zero if it applies. Do not use a trailing zero.)
The Correct Answer and Explanation is:
To determine how many milliliters (mL) of valproic acid syrup the nurse should administer, we can use a simple formula derived from the concentration of the syrup and the required dosage.
Given:
- Required dose of valproic acid: 125 mg
- Concentration of syrup: 250 mg/5 mL
Step 1: Find the concentration in mg/mL.
First, we need to determine how many milligrams are in 1 mL of syrup:Concentration=250 mg5 mL=50 mg/mL\text{Concentration} = \frac{250 \, \text{mg}}{5 \, \text{mL}} = 50 \, \text{mg/mL}Concentration=5mL250mg=50mg/mL
Step 2: Calculate the volume needed for the desired dose.
Now that we know the concentration, we can calculate how many mL are required to achieve the 125 mg dose. The formula to find the volume (V) required is:V=Desired doseConcentration=125 mg50 mg/mLV = \frac{\text{Desired dose}}{\text{Concentration}} = \frac{125 \, \text{mg}}{50 \, \text{mg/mL}}V=ConcentrationDesired dose=50mg/mL125mg
Step 3: Perform the calculation.
Substituting the values into the equation:V=12550=2.5 mLV = \frac{125}{50} = 2.5 \, \text{mL}V=50125=2.5mL
Conclusion:
The nurse should administer 2.5 mL of valproic acid syrup to provide the patient with the required 125 mg dose.
Rounding and Formatting:
As per the instructions, the answer is rounded to the nearest tenth and includes a leading zero, so it is presented as 2.5 mL. There is no trailing zero included, adhering to the formatting requirements.
Clinical Relevance:
Valproic acid is often prescribed for various conditions, including seizure disorders and mood stabilization. It is crucial for nurses to accurately calculate medication dosages to ensure patient safety and therapeutic efficacy. Incorrect dosages can lead to under-treatment or toxicity, necessitating vigilance in the medication administration process.