Therapeutic drug monitoring

Extract Overview Therapeutic drug monitoring is indicated for drugs that have a narrow therapeutic index; in other words, the dose range at which the agent is therapeutic is narrow vs. that above which significant side effects/adverse events of therapy occur. For agents where PK monitoring is possible, and an effective dose range has been defined, this may take the form of assay of drug levels. Where a predictable PD effect is known, this may take the form of assay of a PD marker associated with clinical effect. Indications for PK drug monitoring include: ... Examples of agents where PK assay is currently in clinical use ... Examples of agents where PD effects are monitored Warfarin: narrow therapeutic window between normal INR and INR at a level that risks significant bleeding.