Chapter 2 Flashcards
the four aspects of pharmacokinetics
1.absorption
2. distribution
3. metabolism
4. excretion
Additive effects
Drug interactions in which the effect of a combination of two or more drugs with similar actions is equivalent to the sum of the individual effects of the same drugs given alone. For example, 1 + 1 = 2 (compare with synergistic effects).
Adverse drug event
Any undesirable occurrence related to administering or failing to administer a prescribed medication.
Adverse drug reaction
Any unexpected, unintended, undesired, or excessive response to a medication given at therapeutic dosages (as opposed to overdose).
Adverse effects
A general term for any undesirable effects that are a direct response to one or more drugs.
Agonist
A drug that binds to and stimulates the activity of one or more receptors in the body.
Allergic reaction
An immunologic hypersensitivity reaction resulting from the unusual sensitivity of a patient to a particular medication; a type of adverse drug event.
Antagonist
A drug that binds to and inhibits the activity of one or more receptors in the body. Antagonists are also called inhibitors.
Antagonistic effects
Drug interactions in which the effect of a combination of two or more drugs is less than the sum of the individual effects of the same drugs given alone (1 + 1 equals less than 2); it is usually caused by an antagonizing (blocking or reducing) effect of one drug on another.
Bioavailability
A measure of the extent of drug absorption for a given drug and route (from 0% to 100%).
Biotransformation
One or more biochemical reactions involving a parent drug; occurs mainly in the liver and produces a metabolite that is either inactive or active. Also known as metabolism.
Blood-brain barrier
The barrier system that restricts the passage of various chemicals and microscopic entities (e.g., bacteria, viruses) between the bloodstream and the central nervous system. It still allows for the passage of essential substances such as oxygen.
Chemical name of drug
The name that describes the chemical composition and molecular structure of a drug.
Contraindication
Any condition, especially one related to a disease state or patient characteristic, including current or recent drug therapy, which renders a particular form of treatment improper or undesirable.
Cytochrome P-450
The general name for a large class of enzymes that plays a significant role in drug metabolism and drug interactions.
Dependence
A state in which there is a compulsive or chronic need, as for a drug.
Dissolution
The process by which solid forms of drugs disintegrate in the gastrointestinal tract and become soluble before being absorbed into the circulation.
Drug
Any chemical that affects the physiologic processes of a living organism.
Drug actions
The processes involved in the interaction between a drug and body cells (e.g., the action of a drug on a receptor protein); also called mechanism of action.
Drug classification
A method of grouping drugs; may be based on structure or therapeutic use.
Drug effects
The physiologic reactions of the body to a drug. They can be therapeutic or toxic and describe how the body is affected as a whole by the drug.
Drug-induced teratogenesis
The development of congenital anomalies or defects in the developing fetus caused by the toxic effects of drugs.
Drug interaction
Alteration in the pharmacologic or pharmacokinetic activity of a given drug caused by the presence of one or more additional drugs; it is usually related to effects on the enzymes required for metabolism of the involved drugs.
Duration of action
The length of time the concentration of a drug in the blood or tissues is sufficient to elicit a response.
Enzymes
Protein molecules that catalyze one or more of a variety of biochemical reactions, including those related to the body’s physiologic processes, as well as those related to drug metabolism.