Pharmacology Basics 52 Correctly Answered Questions Latest Update

Which of the following factors will determine the number of drug-receptor complexes formed? A) efficacy of the drug B) receptor affinity for the drug C) Therapeutic index of the drug D) Half-life of the drug E) rate of renal secretion {Ans: The answer is B receptor affinity for the drug will determine the number of drug-receptor complexes formed. Efficacy is the ability of the drug to activate the receptor after binding has occurred. Therapeutic index (TI) is related to safety of the drug. Half-life and secretion are properties of elimination and do not influence formation of drug-receptor complexes.}Which class of drug metabolizing enzymes is located in the microsomal fraction of liver extracts and require the cofactors, iron and NADPH to mono-oxygenate drug molecules. A. Cholinesterase B. Cytochrome P450 C. N-acetyltransferase D. Sulfotransferase E. Transmethylase {Ans: B CYP}Which of the following statements is correct? A. Acidifying the urine accelerates urinary excretion of a weak acid B. Drugs that are quaternary amines are not clinically useful C. Lipophilic drugs must be metabolized to be excreted D. Making the urine more basic accelerates the excretion of drugs that are weak bases E. Most drugs are taken up into cells by endocytosis