therapeutic index

This term is a specialized pharmacological metric used to quantify the safety margin of a medication. A high index indicates a wide safety window where the effective dose is far below the toxic dose, whereas a narrow index signifies that the drug is potentially dangerous because the therapeutic and toxic doses are very close.

In clinical practice, drugs with a narrow therapeutic index require precise dosing and frequent blood-level monitoring to avoid toxicity while maintaining efficacy. This is a technical term used primarily in medicine, pharmacology, and toxicology, and is not used in general conversation.