Therapeutic Window
The range of drug dosages or blood concentrations that produces effective treatment without unacceptable side effects. A wide therapeutic window indicates a large safety margin between the effective and toxic doses. Most peptide drugs have relatively wide therapeutic windows due to their receptor specificity.
Technical Context
The therapeutic window is bounded by the minimum effective concentration (MEC, below which the drug lacks clinical benefit) and the minimum toxic concentration (MTC, above which unacceptable adverse effects occur). A wide therapeutic window (large MTC/MEC ratio) indicates greater dosing flexibility and safety margin. Peptide drugs generally have wide therapeutic windows due to their receptor specificity, though the window may differ by endpoint — for GLP-1 RAs, the therapeutic window for weight management may not be identical to that for glycaemic control. Drugs with narrow therapeutic windows (such as vancomycin) require therapeutic drug monitoring to maintain concentrations within the optimal range.