Individualized dosing in the precision medicine era: a narrative review.

Individualized dosing has become a cornerstone of precision medicine by optimizing therapeutic efficacy while minimizing toxicity through patient-specific dose selection. Traditional approaches, including weight- and body surface area-based dosing, remain fundamental for many medications but are increasingly complemented by pharmacokinetic/pharmacodynamic (PK/PD)-guided strategies and model-informed precision dosing (MIPD). This narrative review summarizes current evidence on individualized dosing across four major therapeutic classes: antimicrobial agents, chemotherapy, monoclonal antibodies and immunotherapies, and anesthetic and critical care agents. It highlights the rationale, advantages, and limitations of conventional dosing approaches while discussing the growing adoption of fixed dosing for selected biologics with predictable pharmacokinetics. The review also examines practical challenges associated with individualized dosing, including dose calculation complexity, medication errors, and operational constraints. Finally, emerging precision-dosing strategies, particularly Bayesian adaptive dosing and biomarker-guided dosing, are discussed as promising approaches to further personalize pharmacotherapy. Collectively, these advances support a shift toward more precise, evidence-based, and patient-centered medication dosing.