How do you calculate the amount of active ingredient in a compounded prescription?

To determine the amount of active ingredient in a compounded prescription, you need to use the formula that involves multiplying the total volume of the compound by the desired concentration of that active ingredient. This relationship illustrates that the amount of the active ingredient is directly related to both the concentration (usually expressed as a percentage or a ratio) and the total volume of the solution you are preparing.

When you multiply the total volume by the desired concentration, you are effectively calculating how much of that volume should consist of the active ingredient in order to achieve the concentration intended for the final product. This is a fundamental concept in compounding, ensuring that the medication delivered has the correct strength for patient safety and efficacy.

In contrast, some of the other options either misrepresent the mathematical relationship or introduce calculations that are not applicable in this context, such as adding or dividing the concentration and volume in a way that does not provide the correct amount of active ingredient needed. Thus, using the equation involving multiplication of total volume by desired concentration is the accurate and appropriate method to arrive at the correct amount of active ingredient needed in a compounded prescription.