When a true trough concentration is requested for a repeatedly dosed drug, when should the specimen generally be collected?
1Immediately after the first dose
2Halfway through specimen centrifugation
3At the expected peak after infusion
4Immediately before the next scheduled dose✓ 정답
해설
A trough is the lowest concentration in a dosing interval and is generally sampled immediately before the next dose once the requested pharmacokinetic conditions are met.