Absorption, distribution, metabolism, and excretion principles and dose-response curve concepts tested on USMLE Step 1, as cloze cards with each term defined.
40 cards · cloze cards · AI-written, checked twice. Edit anything.
- Bioavailability is defined as the ____.
- fraction of an administered dose that reaches the systemic circulation unchanged
- An intravenously administered drug has a bioavailability of ____.
- 100 percent
- First-pass metabolism refers to ____.
- hepatic and intestinal metabolism of an orally absorbed drug before it reaches the systemic circulation
- Volume of distribution (Vd) is defined as ____.
- the amount of drug in the body divided by the plasma drug concentration
- A drug that is highly bound to plasma proteins tends to have a ____ volume of distribution.
- low
- A highly lipophilic drug that distributes extensively into tissues tends to have a ____ volume of distribution.
- high
- The loading dose of a drug is calculated as ____.
- Vd multiplied by target plasma concentration, divided by bioavailability
- The maintenance dose of a drug is calculated as ____.
- clearance multiplied by target plasma concentration, divided by bioavailability
- Half-life is defined as ____.
- the time required for the plasma concentration of a drug to decrease by half
- It takes approximately ____ half-lives for a drug given at a constant rate to reach steady-state plasma concentration.
- 4 to 5
- In zero-order kinetics, ____.
- a constant amount of drug is eliminated per unit time, independent of plasma concentration
- Phenytoin, ethanol, and high-dose aspirin are classic examples of drugs that follow ____ elimination kinetics.
- zero-order
- In first-order kinetics, ____.
- a constant fraction (percentage) of the drug is eliminated per unit time
- Clearance is defined as ____.
- the volume of plasma cleared of drug per unit time
- Clearance can be calculated as ____.
- the rate of drug elimination divided by the plasma drug concentration