Question 74

Two 500 mg doses can be prepared from a 1 g vial of cefazolin.

A 1 g vial of cefazolin contains 1000 mg of the medication. Since each dose is 500 mg, dividing 1000 mg by 500 mg gives us 2 doses.

A) 1.5

This option is incorrect because 1.5 doses would imply that only 750 mg can be used, which does not accurately represent the total amount in a 1 g vial. A 1 g vial provides enough for exactly 2 doses of 500 mg each.

B) 2

This option is correct as a 1 g (1000 mg) vial of cefazolin can be divided into two 500 mg doses. The calculation is straightforward: 1000 mg divided by 500 mg equals 2.

C) 2.5

This option is incorrect because 2.5 doses would suggest that 1250 mg is required, which exceeds the amount available in a 1 g vial. Each dose being 500 mg means only 2 full doses can be extracted.

D) 5

This option is incorrect as it implies that there are 5 doses of 500 mg, which would require a total of 2500 mg. Since the vial only contains 1000 mg, this option is not feasible.

Conclusion

The correct answer is that two 500 mg doses can be prepared from a 1 g vial of cefazolin, as the total amount of cefazolin available allows for exactly two complete doses. All other options either miscalculate the available quantity or exceed it, demonstrating a misunderstanding of dosage calculations.