Which term is the process by which a drug goes from the administration site into the bloodstream?

Which term is the process by which a drug goes from the administration site into the bloodstream?

• A. Distribution
• B. Absorption
• C. Exertion
• D. Sources of drugs

Answer: (B)

Absorption is the process by which a drug moves from its site of administration into the bloodstream. This step determines how much drug reaches systemic circulation and how quickly it appears. For oral medications, the drug must dissolve and cross the gastrointestinal lining, with factors like lipid solubility, whether the drug is ionized at GI pH, and the formulation affecting its ability to cross membranes. The surface area available for absorption (the small intestine has a large area) and the blood flow to the absorption site also influence rate and extent. Some drugs may undergo first-pass metabolism after absorption, reducing the amount that reaches systemic circulation. After absorption, the drug then distributes from the blood into tissues. The other options don’t describe entry into the bloodstream—distribution refers to movement from blood to tissues, exertion isn’t a pharmacokinetic term, and sources of drugs have no relation to this process.

Absorption is the process by which a drug moves from its site of administration into the bloodstream. This step determines how much drug reaches systemic circulation and how quickly it appears. For oral medications, the drug must dissolve and cross the gastrointestinal lining, with factors like lipid solubility, whether the drug is ionized at GI pH, and the formulation affecting its ability to cross membranes. The surface area available for absorption (the small intestine has a large area) and the blood flow to the absorption site also influence rate and extent. Some drugs may undergo first-pass metabolism after absorption, reducing the amount that reaches systemic circulation. After absorption, the drug then distributes from the blood into tissues. The other options don’t describe entry into the bloodstream—distribution refers to movement from blood to tissues, exertion isn’t a pharmacokinetic term, and sources of drugs have no relation to this process.