drugs and the body

  1. Absorption
    what happens to a drug from the time it enters the body until it enters the circulating fluid; intravenous administration causes the drug to directly enter the circulating blood, bypassing the many complications of absorption from other routes
  2. Active Transport
    the movement of substances across a cell membrane against the concentration gradient; this process requires the use of energy biotransformation
  3. Chemotherapeutic agents
    synthetic chemicals used to interfere with the functioning of foreign cell populations; this term is frequently used to refer to the drug therapy of neoplasms, but it also refers to drug therapy affecting any foreign cell
  4. Critical concentration
    the concentration a drug must reach in the tissues that respond to that particular drug to cause the desired effect
  5. Distribution
    movement of a drug to body tissues; the places where a drug may be distributed depend on the drug's solubility, perfusion of the area, cardiac output, and binding of the drug to plasma proteins
  6. Enzyme induction
    process by which the presence of a chemical that is biotransformed by a particular enzyme system in the liver causes increased activity of that enzyme system
  7. Excretion
    removal of a drug from the body; primarily occurs in the kidneys, but can also occur through the skin, lungs, bile, or feces
  8. First-pass effect
    a phenomenon in which drugs given orally are carried directly to the liver after absorption, where they may be largely inactivated by liver enzymes before they can enter the general circulation; oral drugs frequently are given in higher doses than drugs given by other routes because of this early breakdown.
  9. Glomular filtration
    the passage of water and water-soluble components from the plasma into the renal tubule
  10. Half-life
    the time it takes for the amount of drug in the body to decrease to one half of the peak level it previously achieved
  11. Hepatic microsomal system
    liver enzymes tightly packed together in the hepatic intracellular structure, responsible for the biotransformation of chemicals, including drugs
  12. Loading dose
    use of a higher dose than that which is usually used for treatment to allow the drug to reach the critical concentration sooner
  13. Passive diffusion
    movement of substances across a semi-permeable membrane with the concentration gradient; this process does not require energy
  14. Pharmacodynamics
    the science that deals with the interaction and the foreign chemicals, including drugs, that enter living organisms; the way a drug affects a body
  15. Pharmacokinetics
    the way the body deals with a drug, including absorption, distribution, biotransformation, and excretion
  16. Placebo effect
    documented effect on the mind of a drug therapy; if a person perceives that a drug will be effective, the drug is much more likely to actually be effective
  17. Receptor sites
    specific areas on cell membranes that react with certain chemicals to cause an effect within the cell
  18. Selective toxicity
    property of a chemotherapeutic agent that affects only systems found in foreign cells without affecting healthy human cells (e.g., specific systems used by bacteria but not by human cells)
Card Set
drugs and the body
Chapter 2 Karch