Question

Claforan (cefotaxime sodium) 750 mg IM q8hrs. The directions in the package insert for the 1 g vial state: “For IM administration add 3 ml of diluent, approximate withdrawable volume 3.4 mL, approximate concentration 300mg/mL.” How many milliliters will you administer?

Answer 1

To 1 g of the material we are adding 3 ml of diluent to give a withdrawable of 3.4 ml. The final concentration mentioned is 300 mg/ml which means that every ml of the final liquid will have 300 mg of the Claforan compound. Since we need to administer 750 mg, the way to do this calculation is to find out how many ml will have 750 mg.

Since 1 ml will have 300 mg

750 mg will be present in

750 mg x 1 ml/ 300 mg

The final answer will be 2.5 ml.

So if you administer 2.5 ml you will have administered 750 mg of Claforan.