Terminal Half-Life
When multiple doses of the drug are given
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the drug accumulates in various body tissues apart from blood
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when we stop giving the drug
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plasma concentration of the drug falls due to elimination
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drug starts diffusing back from its storage sites into the plasma
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plasma half-life of the drug gets prolonged as compared to that during steady state.
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half-life during the terminal stage of elimination is called terminal half-life.
E.g. for gentamicin, half-life during steady state is about 3 hours but the terminal half-life is about 50 hours