A provider orders 3 mg granisetron HCL oral solution. The supply on hand is 2 mg per 10 mL. How many milliliters should be administered?

A provider orders 3 mg granisetron HCL oral solution. The supply on hand is 2 mg per 10 mL. How many milliliters should be administered?

• A. 15 mL
• B. 10 mL
• C. 5 mL
• D. 20 mL

Answer: (A)

When you fill a dose from a solution, you convert the ordered milligrams into the volume using the solution’s concentration. Here, the granisetron is 2 mg in 10 mL, which is 0.2 mg per mL. To deliver 3 mg, divide the dose by the concentration: 3 mg ÷ 0.2 mg/mL = 15 mL. An equivalent way is a proportion: 2 mg/10 mL = 3 mg/x mL, giving x = 15 mL. Therefore, administer 15 mL.

When you fill a dose from a solution, you convert the ordered milligrams into the volume using the solution’s concentration. Here, the granisetron is 2 mg in 10 mL, which is 0.2 mg per mL. To deliver 3 mg, divide the dose by the concentration: 3 mg ÷ 0.2 mg/mL = 15 mL. An equivalent way is a proportion: 2 mg/10 mL = 3 mg/x mL, giving x = 15 mL. Therefore, administer 15 mL.