Pharmacokinetics Quiz Questions

Pharmacology

• Streptomycin inhibits binding of penicillin to bacterial cell wall.

Mechanisms of Drug Action

• The most common mechanism of drug action is a chemical mechanism.

Pharmacogenetics and Adverse Drug Reactions

• All or non-response curve is used to calculate potency.
• Salbutamol tolerance in bronchial asthma is due to down regulation of beta-2 receptors.
• Type B adverse drug reactions are pharmacogenetic effects.

Receptors and Signaling

• Corticosteroid receptors are cytoplasmic receptors that control transcription.
• Drugs need to bind to receptors on the target cell to produce their actions.
• The fastest signaling mechanism is the ion channel mechanism.

Pharmacokinetics

• The maximal effect of the drug occurs only when the drug binds to spare receptors.
• Sublingual route of administration completely bypasses hepatic first-pass metabolism.
• The best dose interval is half-life to avoid drug concentration fluctuations.
• In zero-order kinetics, the graph of the drug concentration against time is a straight line.
• Pharmacokinetics include absorption, elimination, and distribution, but not actions.
• Half-life is the time after which plasma drug concentration is halved.

Agonists and Antagonists

• A full agonist is a drug that possesses both affinity and efficacy.
• A systemic clearance is the sum of individual organ clearances.

Metabolism and Excretion

• The most famous site for first-pass metabolism is the liver.
• The drug that is mostly eliminated by glomerular filtration is lithium.
• Lipophilic drugs can enter the CNS easily.
• Competitive antagonist at muscarinic receptors is atropine.

Pharmacological Curves

• The inverse agonist is a drug that possesses affinity and reversed efficacy.
• All-or-none response curve differs from the graded curve in that it depicts the percentage of responders against the dose.
• Efficacy of graded dose-response curve is obtained from Emax.

Tolerance and Pharmacokinetic Interactions

• Tolerance-unlike tachyphylaxis-to drugs may be due to counter-regulatory mechanisms.
• Pharmacokinetic drug interactions may be due to enzyme induction.
• Penicillin should not be mixed with aminoglycoside antibiotics in the same syringe because streptomycin inactivates penicillin.

Absorption and Distribution

• The most common method of drug absorption is passive diffusion.
• In first-order kinetics, the concentration-time relationship is described by an exponential equation.
• Pharmacokinetics is defined as the movement of drugs into, around, and out of the body.

Enzymes and Metabolism

• The most important enzyme for drug metabolism is CYT P450 oxidase.
• Bioavailability of intravenous-administered drugs is equal to 1.
• Excretion of drugs by filtration is affected by pH of urine and glomerular filtration rate.
• Absorption of oral drugs is not affected by capillary permeability or blood supply of the absorptive surface.

Test your knowledge on pharmacokinetics with these quiz questions covering topics such as routes of administration, dose interval determination, and zero order kinetics. Choose the correct answers to enhance your understanding of drug metabolism in the body.