What is the point of peaks and troughs in vancomycin?

• A. To maintain adequate drug levels for effectiveness
• B. To measure kidney function
• C. To monitor liver enzymes
• D. To check blood glucose

Answer: (A)

Vancomycin dosing relies on therapeutic drug monitoring because you want enough drug in the body to kill the bacteria, but not so much that it harms the patient. The trough is the lowest concentration just before the next dose and is used to ensure there is still enough drug present to maintain effectiveness over the dosing interval. If the trough is subtherapeutic, the infection may not be adequately treated, so the dose or interval is adjusted. The peak, the highest concentration after a dose, helps guard against toxicity by making sure the dose isn’t excessively high. In practice, trough monitoring is the primary tool for routine adjustment, with peaks checked in certain situations. Overall, the goal is to keep vancomycin exposure within a safe, effective range to treat the infection effectively while minimizing kidney or other toxicity.