What must be done to the needle before injecting using the Z-track method?

When using the Z-track method for intramuscular injections, it is essential to change the needle after drawing up the medication. This practice is crucial for a couple of reasons. First, it ensures that the needle is sharp and free from any potential contaminants that may have come from the vial or the drawing process. A sharp needle creates a smaller and cleaner entry point into the muscle, which facilitates less discomfort for the patient.

Additionally, the Z-track method itself involves displacing the skin and subcutaneous tissue to create a z-pattern that seals the medication deep in the muscle. Changing the needle allows the clinician to maintain the integrity of the medication and optimize the delivery method, as the new needle is less likely to introduce any debris or compromise the medication's effectiveness.

The other options involve varying the gauge of the needle or sterilizing it, which are not necessary steps specific to the Z-track technique. The focus is primarily on ensuring a proper injection technique with a clean, new needle.