A nurse is preparing to administer digoxin 0.15 mg PO. Available is digoxin elixir 0.05 mg/mL. 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.)
The Correct answer and Explanation is:
To determine how many milliliters (mL) of digoxin elixir the nurse should administer, we can use the following formula for dosage calculation:
[
\text{Volume to administer (mL)} = \frac{\text{Desired Dose (mg)}}{\text{Concentration (mg/mL)}}
]
Given:
- Desired Dose: 0.15 mg
- Concentration: 0.05 mg/mL
Now, substituting the values into the formula:
[
\text{Volume to administer (mL)} = \frac{0.15 \text{ mg}}{0.05 \text{ mg/mL}} = 3 \text{ mL}
]
Thus, the nurse should administer 3 mL of digoxin elixir.
Explanation:
- Understanding the Units:
The nurse is tasked with administering digoxin, a cardiac glycoside used for heart conditions. The prescribed dosage of digoxin is 0.15 mg. The available formulation is a liquid elixir that contains 0.05 mg of digoxin in each mL. - Setting Up the Calculation:
To find out how much of the elixir to administer, it’s essential to divide the total required dosage by the concentration of the medication. This approach ensures that the calculation aligns with the principles of pharmacology, where dosages must be converted to compatible units. - Performing the Calculation:
The calculation shows that for every mL of elixir, there is 0.05 mg of digoxin. To find out how many mL are needed for 0.15 mg, we divide the desired amount (0.15 mg) by the concentration (0.05 mg/mL), resulting in 3 mL. - Rounding and Reporting:
The instruction specifies rounding to the nearest whole number, which in this case remains 3 mL. It’s also important to follow proper guidelines for reporting doses, such as using a leading zero (0.3 mL), but in this instance, the whole number does not require additional formatting.
In summary, the correct volume to administer is 3 mL of digoxin elixir. This ensures the patient receives the correct therapeutic dose while adhering to safe medication administration practices.