Once administered, drugs undergo four stages within the body absorption, distribution, metabolism and excretion.
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Absorption Drugs are absorbed from the site of administration into the bodyu2019s circulation system. They enter the body via various routes such as, oral (mouth), nose, eyes, ears, skin, vaginally, rectally. Oral drugs are transported to the liver via blood vessels to be broken down.
Distribution Distribution of drugs happens through the blood stream.u00a0
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Metabolism Metabolism is the process through which a drug is broken down by enzymes in the liver into an enzymatic product which is less active than itu2019s original component.
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Excretion Excretion is the final stage of itu2019s time in the body. This happens via urine and faeces.