How should you handle mixing vaccines with regard to quantity?

• A. Mix as much as you have storage for and save leftovers.
• B. Mix enough for several days.
• C. Determine how many you will vaccinate and only mix enough to vaccinate that number; leftovers should be discarded.
• D. Always mix all that you need for the week.

Answer: (C)

Only mix the amount you will use in the session. Once a vaccine is reconstituted, its potency can decline quickly and it becomes more susceptible to contamination, so you should discard any leftovers according to the product label. By estimating how many animals you plan to vaccinate and preparing just that amount, you reduce waste and protect safety and effectiveness. Some vaccines have a strict use window after mixing, so following the label’s timing guidance is essential. If your numbers change, start fresh with a new vial rather than keeping leftovers.