Therapeutic Index (TI)

Introduction to Therapeutic Index (TI) Calculator

The therapeutic index (TI) is a comparison of the amount of a therapeutic agent that causes the therapeutic effect to the amount that causes toxicity. It is calculated by dividing the toxic dose (TD50) by the effective dose (ED50). The resulting value provides an indication of the relative safety of the drug. In this formula, TI represents the therapeutic index, TD50 is the dose at which 50% of the population experiences toxic effects, and ED50 is the dose at which 50% of the population experiences the desired therapeutic effect.

Parameter usage:

• TD50= toxic dose at which 50% experience toxic effects
• ED50= effective dose at which 50% experience therapeutic effects

Output:

• TI= therapeutic index

Data validation

The TD50 and ED50 values are expected to be greater than zero for valid results.

Summary

This calculator helps determine the therapeutic index of a drug, providing insight into its relative safety profile based on the comparison between toxic and therapeutic doses.