A pharmacy technician receives a prescription for insulin 100 units/mL with instructions to inject 30 units daily for 28 days. How many 3 mL vials should the technician plan to dispense?

To determine how many 3 mL vials of insulin are required for the prescription, you first need to calculate the total volume of insulin needed for the 28-day treatment period. The patient is instructed to inject 30 units of insulin daily.

Over 28 days, the total insulin needed is calculated as follows:

30 units/day × 28 days = 840 units total

Since the concentration of insulin is 100 units/mL, you can find out the total volume needed by dividing the total units by the concentration:

840 units ÷ 100 units/mL = 8.4 mL

Next, since insulin is to be dispensed in 3 mL vials, we need to determine how many vials are needed to cover the 8.4 mL required:

8.4 mL ÷ 3 mL/vial = 2.8 vials

Since you cannot dispense a fraction of a vial, you round up to the nearest whole number. This means the technician will need a total of 3 vials to ensure the patient has enough insulin for the entire duration of the treatment.

Thus, the correct amount to dispense is 3 vials, allowing for proper dosing without patient shortages