Drug Half-Life from Clearance and Volume of Distribution

Introduction to Drug Half-Life from Clearance and Volume of Distribution

The half-life of a drug is calculated as the time required for the concentration or amount of the drug in the body to be reduced by 50%. According to the pharmacokinetic principles, the half-life can be calculated using the volume of distribution and clearance of the drug. In this formula, Half-life represents the time required for the concentration of the drug to decrease by 50%, Volume of Distribution is the theoretical volume that the total amount of drug would have to occupy to provide the same concentration as it is in the blood plasma, and Clearance is the volume of plasma from which the drug is completely removed per unit time. The result is expressed in time units, such as hours or minutes.

Parameter usage:

• Volume of Distribution= theoretical volume for the same concentration
• Clearance= volume of plasma cleared per unit time

Output:

• Half-life= time required for drug concentration to reduce by 50%

Data validation

The numbers should be greater than zero.

Summary

This calculator takes into account the volume of distribution and clearance of a drug and outputs its half-life. It is fundamental in pharmacology to determine the persistence of a drug in the body.