Allopurinol 250 mg IV per day is prescribed. The supply is 500 mg per vial. How many vials are required to achieve the daily dose?

Allopurinol 250 mg IV per day is prescribed. The supply is 500 mg per vial. How many vials are required to achieve the daily dose?

• A. 0.25 vial
• B. 0.5 vial
• C. 1 vial
• D. 1.5 vial

Answer: (B)

To figure out how many vials are needed, compare the prescribed amount to what’s in each vial. The daily dose is 250 mg, and each vial contains 500 mg. Dividing 250 mg by 500 mg per vial gives 0.5, meaning half of a vial is required to deliver the daily dose. In practice, you would use half of the vial’s content, depending on pharmacy policies about partial vial use.

To figure out how many vials are needed, compare the prescribed amount to what’s in each vial. The daily dose is 250 mg, and each vial contains 500 mg. Dividing 250 mg by 500 mg per vial gives 0.5, meaning half of a vial is required to deliver the daily dose. In practice, you would use half of the vial’s content, depending on pharmacy policies about partial vial use.