What is Peak and Trough in relation to Antibiotic Therapy?

Answer 1

Peak and trough are methods used to establish the effectiveness of a drug. Peak is drawing the serum blood levels after the drug is administered as it distributes rapidly and reaches its peak in therapeutic range. Trough is drawing the serum blood levels right before the next dose. Trough is the lowest drug level that is needed to reach therapeutic range. If trough is > than normal, the patient is at risk for adverse effects. Therefore, the doctor should expand the time interval before ordering the next dose or decrease drug dose. In general, a trough is usually drawn one hour prior to start infusion and the peak about one hour after the infusion finished. The are times when the physician orders the trough drawn immediately prior to an infusion (ie Vancomycin).

Answer 2

This relates to when you are taking your doses. A peak occurs about an hour after a dose, if taken orally, and the trough is when you are due for another dose. Imagine a graph of how much medication is in your body. It would look like waves, the tops of the waves are peaks, the bottom are troughs.

Answer 3

A Peak and Trough is a lab test to determine the levels of medication in the blood, and if they are in the therapeutic range. A peak, drawn shortly after the medication has infused, will tell how much is being used. A trough, drawn shortly before the medication is administered, will tell how much medication is left from the last dose.