A nurse is preparing to administer levothyroxine 5 mcg/kg PO to a client who weighs 220 lb. Available is levothyroxine 75 mcg tablets. How many tablets 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 the number of levothyroxine tablets to administer, follow these steps:
- Convert the client’s weight from pounds to kilograms:
- Weight in pounds: 220 lb
- Conversion factor: 1 lb = 0.453592 kg
- Weight in kilograms = 220 lb × 0.453592 kg/lb = 99.79 kg (rounded to 2 decimal places)
- Calculate the total dose of levothyroxine required in micrograms:
- Dose ordered: 5 mcg/kg
- Weight in kilograms: 99.79 kg
- Total dose = 5 mcg/kg × 99.79 kg = 498.95 mcg
- Determine how many tablets are needed to provide this dose:
- Available tablet strength: 75 mcg per tablet
- Number of tablets = Total dose / Tablet strength
- Number of tablets = 498.95 mcg / 75 mcg/tablet = 6.651
- Round to the nearest whole number:
- 6.651 rounded to the nearest whole number is 7 tablets.
Therefore, the nurse should administer 7 tablets of levothyroxine.
Explanation:
- Weight Conversion: The weight conversion from pounds to kilograms is crucial because the medication dose is calculated per kilogram of body weight. Accurate conversion ensures that the dosage is appropriate for the client’s weight.
- Dose Calculation: The dose of levothyroxine is based on the client’s weight. By multiplying the weight in kilograms by the dose per kilogram, we get the total dose required.
- Tablet Calculation: Knowing the strength of each tablet allows us to determine how many tablets are necessary to meet the total dose requirement.
- Rounding: In clinical settings, doses are typically rounded to the nearest whole number to ensure practical and safe administration.
In this case, rounding 6.651 to the nearest whole number gives us 7 tablets. This process ensures the client receives the correct amount of medication while considering practical aspects of tablet administration.