elimination half-life

The biological half-life of a substance is the time required for half of that substance to be removed from an organism by either a physical or a chemical process. Biological half-life is an important pharmacokinetic parameter and is usually denoted by the abbreviation t1/2.While a radioactive substance decays perfectly according to first order kinetics where the rate constant is fixed, the elimination of a substance from a living organism follows more complex kinetics. See the article rate equation.
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