Question

Explain how you would prepare the following prescription using a vial containing 17000 U of Drug F powder and a vial containing sodium chloride for injection

Drug F 800 U per mL

Sodium Chloride Injection 10 mL

sig. For IM Injection

Answer 1

The available concentration of Drug F = 17000 U

We need concentration = 800 U/mL

Volume of NaCl to be added to drug vial = 17000U/800U/mL = 21.25 mL

So to obtain the required concentration of a drug F, add 21.25mL of NaCl injection solution to the drug vial. This will provide the desired concentration =  800 U/mL

Let's confirm the concentration by doing back calculations:

We have 17000 U drug and we are adding 21.25mL of NaCl solution.

So the concentration of drug = 17000 u / 21.25 mL = 800 U/mL