Use Therapeutic Window Width when you need to measure the width of the therapeutic window as the toxic blood threshold minus the effective blood threshold, both in milligrams per decilitre. Enter Effective threshold and Toxic threshold using the definitions and units below so the result can be reproduced.

Effective threshold

Lowest concentration with therapeutic effect, in mg/dL.

Toxic threshold

Lowest concentration with toxic effects, in mg/dL; must exceed the effective threshold.

The published tool contract uses this rule: Measure the width of the therapeutic window as the toxic blood threshold minus the effective blood threshold, both in milligrams per decilitre.

Window width

Width of the therapeutic range in mg/dL.

The calculation does not propagate measurement uncertainty, sampling error, or biological and chemical variability. It is informational and cannot diagnose a condition, select treatment, or replace professional interpretation of the original measurements.

Retain the original Effective threshold and Toxic threshold values and their units alongside the result. Therapeutic Index is useful when you instead need to compute the ratio of the toxic dose TD50 to the effective dose ED50. RDW-CV Percent provides another view by helping you compute red cell distribution width CV from RBC volume standard deviation and MCV.

• Therapeutic Index

  Compute the ratio of the toxic dose TD50 to the effective dose ED50.

• RDW-CV Percent

  Compute red cell distribution width CV from RBC volume standard deviation and MCV.

• Selectivity Index

  Compute the ratio of toxic IC50 to therapeutic IC50 for a compound.