After a drug is administered, it goes through how many stages?

After a drug is administered, it goes through how many stages?

• A. 3
• B. 4
• C. 5
• D. 2

Answer: (B)

After a drug is given, it follows four main stages: absorption, distribution, metabolism, and excretion. Absorption is how the drug enters the bloodstream from the administration site. Distribution describes how it travels through the blood to reach tissues and organs where it can act or be stored. Metabolism, usually occurring in the liver, chemically transforms the drug into forms easier to eliminate. Excretion is the removal of the drug and its metabolites from the body, primarily through the kidneys in urine, with other routes like the liver (bile), lungs, or sweat possible. This four-step process, often referred to as ADME, explains both how quickly a drug begins to work and how long it stays active. While some texts group excretion differently, the standard model uses four stages, which is why four is the correct count.

After a drug is given, it follows four main stages: absorption, distribution, metabolism, and excretion. Absorption is how the drug enters the bloodstream from the administration site. Distribution describes how it travels through the blood to reach tissues and organs where it can act or be stored. Metabolism, usually occurring in the liver, chemically transforms the drug into forms easier to eliminate. Excretion is the removal of the drug and its metabolites from the body, primarily through the kidneys in urine, with other routes like the liver (bile), lungs, or sweat possible. This four-step process, often referred to as ADME, explains both how quickly a drug begins to work and how long it stays active. While some texts group excretion differently, the standard model uses four stages, which is why four is the correct count.