Which statement about therapeutic drug monitoring is true?

Which statement about therapeutic drug monitoring is true?

• A. It ignores individual variation
• B. It uses sampling to keep drug exposure within a target range
• C. It is used only for antibiotics
• D. It is performed only after toxicity occurs

Answer: (B)

Therapeutic drug monitoring focuses on tailoring drug therapy to the individual by measuring drug levels in the blood and adjusting the dose to keep exposure within a predefined target range. Because people differ in how they absorb, distribute, metabolize, and eliminate drugs, the same dose can lead to subtherapeutic or toxic levels. By taking samples at the right times (such as troughs, peaks, or using PK models to estimate exposure like AUC) and comparing them to a target range, clinicians adjust dose or dosing interval to maintain efficacy while minimizing toxicity. This approach isn’t limited to antibiotics; many drugs—anticonvulsants, immunosuppressants, and others with narrow therapeutic windows—rely on TDM. It’s also not performed only after toxicity occurs; monitoring is used throughout therapy, including at initiation and after dose changes, to prevent toxicity and ensure the desired effect.

Therapeutic drug monitoring focuses on tailoring drug therapy to the individual by measuring drug levels in the blood and adjusting the dose to keep exposure within a predefined target range. Because people differ in how they absorb, distribute, metabolize, and eliminate drugs, the same dose can lead to subtherapeutic or toxic levels. By taking samples at the right times (such as troughs, peaks, or using PK models to estimate exposure like AUC) and comparing them to a target range, clinicians adjust dose or dosing interval to maintain efficacy while minimizing toxicity.

This approach isn’t limited to antibiotics; many drugs—anticonvulsants, immunosuppressants, and others with narrow therapeutic windows—rely on TDM. It’s also not performed only after toxicity occurs; monitoring is used throughout therapy, including at initiation and after dose changes, to prevent toxicity and ensure the desired effect.