The half-life of a drug is the time taken for the plasma concentration of a drug to reduce to half its original value. Half-life is used to estimate how long it takes for a drug to be removed from your body. For example: The half-life of Ambien is about 2 hours.
half-life [haf´līf″] the time required for the decay of half of a sample of particles of a radionuclide or elementary particle; see also radioactivity. Symbol t½ or T½. half-life (haf'līf), The period in which the radioactivity or number of atoms of a radioactive substance decreases by half; similarly applied to any substance, such as a drug in.
Half-Life Definition: The time required to convert one half of a reactant to product. The term is commonly applied to radioactive decay, where the reactant is the parent isotope and the product is .
The Half Life of Caffeine How long will caffeine be in my system? Caffeine has become the hot-topic of the moment. Its addition to so many products makes it important to know how long caffeine sticks around in the body in order to prevent possible overdose.. Caffeine takes a certain amount of time to work through your system.