Final answer:
Z-track injections are used to administer medications intramuscularly, preventing leakage into the subcutaneous tissue. Oral medications are convenient for home use, but when absorption is an issue, intramuscular or intravenous routes may be used, usually in a healthcare setting.
Step-by-step explanation:
Z-track injections are a method of administering medication deep into the muscle. This technique is designed to prevent leakage of the medication into the subcutaneous tissue. Given this information, intramuscular (a) is the type of medication administered by Z-track injection.
Regarding the administration of antimicrobial medication to treat a systemic infection, if home administration is appropriate and convenient, oral (A) medication would typically be used. However, when the medication is not adequately absorbed in the gastrointestinal (GI) tract, a parenteral route, which includes both intramuscular and intravenous injections, might be preferred. Intramuscular administration is often conducted in healthcare settings due to the need for specific techniques, like the Z-track, to administer the drugs properly.
It's important to note that intravenous administration often achieves higher plasma levels of medication more rapidly than oral or intramuscular routes. This can be an important factor in deciding the administration route for treating infections.