A nurse is going to administer medicines to a patient who weighs 50 kg and is to be given inj. ceftriaxone at 50 mg/kg BD. The available stock strength is 500 mg/vial. How many vials of drugs does the nurse need for the morning dose of medication?

1. A

   5 vials

2. B

   8 vials

3. C

   10 vials

4. D

   2.5 vials

Appeared in: DSSSB October 2024

Explanation

• The first step is to calculate the total dose required for a single administration based on the patient's weight.
• Calculation: 50 mg/kg × 50 kg = 2500 mg. This is the total amount of ceftriaxone needed for one dose.
• The term 'BD' (bis in die) means twice a day, but the question specifically asks for the quantity needed for the single 'morning dose'.
• The final step is to determine how many vials are needed to supply the 2500 mg dose.
• Calculation: 2500 mg (required dose) ÷ 500 mg/vial (stock strength) = 5 vials.

Why Other Options Were Wrong

• Option B: This option represents an incorrect calculation. 8 vials would provide 4000 mg (8 vials × 500 mg/vial), which is significantly higher than the prescribed dose.
• Option C: This represents the total number of vials needed for the entire day (24 hours), not for a single dose as requested.
• Option D: This is half of the correct dose. This calculation might result from mistakenly halving the dose per kg or misinterpreting the order.

Related Visual

Clinical Relevance

• Nursing practice connection: Use the key finding related to Drug Dosage Calculation to guide bedside assessment, documentation, and the next nursing action.
• Accurate drug calculation is a fundamental nursing responsibility critical for patient safety. Errors can lead to underdosing (ineffective treatment) or overdosing (toxicity).
• Always adhere to the 'Five Rights' of medication administration: Right Patient, Right Drug, Right Dose, Right Route, and Right Time.
• In clinical practice, many institutions require a second nurse to independently verify dose calculations for certain medications to prevent errors.

How to Approach the Question

• First, identify all the given information: patient's weight (50 kg), prescribed dose (50 mg/kg BD), and available stock (500 mg/vial).
• Carefully read the question to determine what is being asked. Here, it is the number of vials for a single 'morning dose'.
• Recognize that 'BD' means twice daily, so the 50 mg/kg is the amount for each dose, not the total for the day.
• Calculate the total milligrams needed for one dose: Multiply the patient's weight by the prescribed dose per kilogram.
• Finally, divide the total milligrams needed by the milligrams available per vial to find the number of vials required.

Concept Tested & Keywords

• Concept Tested: Drug Dosage Calculation
• Stem keywords: administer medicines, patient weighs 50 kg, inj. ceftriaxone, 50 mg/kg BD, 500 mg/vial, morning dose
• Lead-in keywords: How many

Question ID

Qu4pAS_FlG8HWq8apXFyoI

Copy ID

Reference Book

E6 Pharmacology Nurses Shanbhag 3e p. 51-53