If a pharmacy technician dilutes a 1 g vial of cefazolin (Ancef) to a concentration of 100 mg/ml, what volume is needed to prepare a 500 mg dose?

To determine the volume required to prepare a 500 mg dose of cefazolin when it has been diluted to a concentration of 100 mg/ml, it is important to use the formula that relates dose, concentration, and volume.

The formula is:

[ \text{Volume} = \frac{\text{Dose}}{\text{Concentration}} ]

In this case, we have a dose of 500 mg and a concentration of 100 mg/ml. By substituting these values into the formula, we can find the required volume:

[ \text{Volume} = \frac{500 , \text{mg}}{100 , \text{mg/ml}} ]

Calculating this gives:

[ \text{Volume} = 5 , \text{ml} ]

This indicates that to obtain a dose of 500 mg of cefazolin from a solution that has a concentration of 100 mg/ml, you would need to measure out 5 ml of the diluted solution.

Understanding the relationship between dose and concentration is crucial in pharmacy practice, as it ensures that the correct amount of medication is administered to patients. This calculation reinforces the importance of dosage forms and concentrations when preparing medications in various clinical settings.