What is the purpose of adding air in the air lock technique?

The purpose of adding air in the air lock technique is to create a seal within the syringe that helps to keep the medication within the muscle tissue. When medication is injected into the muscle, the air bubble prevents the medication from leaking back out of the injection site, ensuring that the full dose is delivered effectively and absorbed as intended. This technique is particularly useful in intramuscular injections, where a proper seal can enhance the medication's effectiveness and minimize the risk of leakage or contamination.

While other options may seem plausible, they do not accurately reflect the function of the air lock technique. For example, reducing the volume of medication or acting as a dispersing agent are not the primary considerations of this method, nor does it inherently ensure that medication is delivered faster.