Therapeutic Drug Monitoring Lecture 1: Clinical Pharmacokinetics and Volume of Distribution

Linear pharmacokinetics

15 μg/mL

Nonlinear pharmacokinetics

<p>Saturable or Michaelis-Menten pharmacokinetics</p> Signup and view all the answers

<p>Phenytoin and salicylic acid</p> Signup and view all the answers

<p>Incomplete absorption or decreased bioavailability</p> Signup and view all the answers

<p>It is highly bound to serum albumin.</p> Signup and view all the answers

<p>It is highly bound to tissues, primarily muscle.</p> Signup and view all the answers

<p>Time required for serum concentrations to decrease by one-half after absorption and distribution phases are complete.</p> Signup and view all the answers

<p>How quickly drug serum concentrations decline in a patient.</p> Signup and view all the answers

<p>t1/2 = 0.693/ke</p> Signup and view all the answers

<p>It determines the time to reach steady state during continuous dosing and the dosage interval.</p> Signup and view all the answers

<p>Reciprocal time (hour−1, minute−1, day−1, etc.)</p> Signup and view all the answers

<p>The terminal slope of the serum concentration/time curve after absorption and distribution phases are complete.</p> Signup and view all the answers

<p>Increase less than expected</p> Signup and view all the answers

<p>Increase their own rate of metabolism (autoinduction)</p> Signup and view all the answers

<p>MD = Css ⋅ Cl</p> Signup and view all the answers

<p>Range of steady-state concentrations that produce desired effects without adverse effects</p> Signup and view all the answers

<p>10–20 μg/mL</p> Signup and view all the answers

<p>Determines the maintenance dose required for a given steady-state serum concentration</p> Signup and view all the answers

<p>Easy to compute the required maintenance dose</p> Signup and view all the answers

<p>8–12 μg/mL</p> Signup and view all the answers

<p>The volume of distribution determines the loading dose required to achieve a desired steady-state drug concentration immediately after administration.</p> Signup and view all the answers

<p>The patient with a smaller volume of distribution will have a higher serum concentration compared to the patient with a larger volume of distribution.</p> Signup and view all the answers

<p>Warfarin has a very small volume of distribution of 5-7 L because it is primarily contained in the blood and does not distribute widely in the body tissues.</p> Signup and view all the answers

<p>Digoxin has a very large volume of distribution of 500 L because it distributes widely in the body and binds extensively to bodily tissues.</p> Signup and view all the answers

<p>The extent to which a drug binds in the blood or serum compared to its binding in tissues is an important determinant of its volume of distribution.</p> Signup and view all the answers

<p>If a drug has a large volume of distribution, a larger loading dose will be required to achieve a desired steady-state concentration.</p> Signup and view all the answers

<p>The volume of distribution is a crucial parameter in determining the appropriate loading dose to rapidly achieve the desired steady-state drug concentration, which is essential for effective and safe drug therapy.</p> Signup and view all the answers

<p>A highly lipophilic (fat-soluble) drug would generally have a larger volume of distribution compared to a hydrophilic (water-soluble) drug because lipophilic drugs can distribute more extensively into fatty tissues.</p> Signup and view all the answers

<p>Pharmacokinetics is what the body does to the drug, while pharmacodynamics is what the drug does to the body.</p> Signup and view all the answers

<p>The volume of distribution is used to calculate the loading dose of a drug needed to achieve a target concentration.</p> Signup and view all the answers

<p>Steady state is the condition where the rate of drug administration equals the rate of drug removal, and the amount of drug in the body reaches a constant value.</p> Signup and view all the answers

<p>Steady-state drug concentrations are used to assess patient response and compute new dosage regimens, as they represent the equilibrium condition where drug levels are constant.</p> Signup and view all the answers

<p>In linear pharmacokinetics, drug concentrations increase proportionally with the dose, while in nonlinear pharmacokinetics, drug concentrations increase disproportionately with the dose.</p> Signup and view all the answers

<p>A continuous intravenous infusion can achieve steady-state drug concentrations, as the rate of drug administration equals the rate of drug removal.</p> Signup and view all the answers

<p>Administering an oral medication every 12 hours can also achieve steady-state drug concentrations, as the rate of drug administration equals the rate of drug removal.</p> Signup and view all the answers

<p>Steady-state drug concentrations are used to compute new dosage regimens, as they represent the equilibrium condition where drug levels are constant and can be used to predict the response to changes in dosing.</p> Signup and view all the answers