[Revision] Pharmacokinetics

Which statement about the process of drug discovery is true?

• It only encompasses the non-clinical laboratory and animal testing.

• It is the process which ascertains the effectiveness and safety of potential drug candidates.

• It is the process by which therapeutic compounds are formulated into medicines.

• It ensures there are no side-effects associated with the potential drug candidates

What are the protein structures called that are expressed within the cell membranes and interact with endogenous signalling molecules or some drugs to initiate an intracellular response?

• Enzymes

• Hormones

• Ligands

• Receptors

What are adverse drug reactions (ADRs)?

• The synergistic effects that are seen when some drugs are administered concurrently.

• Responses to increased drug doses required to achieve the same physiological outcome.

• Unintended alternative physiological responses caused by the drug that cause harm to the patient.

• Harmful chemical interactions between two drugs that are used to treat the same clinical symptoms.

In pharmacokinetics what does the acronym ADME stand for?

• Absorption, Distribution, Metabolism, and Excretion

• Administration, Differentiation, Metabolism, and Excretion

• Absorption, Disintegration, Metabolism, and Efficacy

• Administration, Distribution, Metabolism, and Efficacy

Which of the following is the correct definition of bioavailability?

• Bioavailability describes the proportion of the drug administered that is metabolised very quickly and thus is not available to induce a physiological effect.

• Bioavailability describes the ability of the administered drug metabolites to cause undesirable physiological effects.

• Bioavailability is used to describe the fraction of the dose of drug administered that is present within the body and facilitates the desired physiological effects.

• Bioavailability is the length of time an administered drug is present in the body and thus is available to cause a physiological effect.

Given the information shown in the figure below, which of the following statements is correct?

• Drug A has the most appropriate pharmacodynamic properties of the three drugs shown as it reaches maximal efficacy within the therapeutic window.

• Drug B has the most appropriate pharmacodynamic properties of the three drugs shown as a range of its plasma concentrations are within the therapeutic window.

• Drug C has the most appropriate pharmacodynamic properties of the three drugs shown as non-toxic effects are achieved within the therapeutic window.

• All three drugs have appropriate pharmacodynamic properties as they all achieve maximal physiological effects and have concentrations within the therapeutic window.

Which of the following statements best describes pharmacodynamics?

• The study of how drugs reach their target in the body and how the levels of a drug in the blood are affected by absorption, distribution, metabolism and excretion.

• The study of how drugs can be designed using molecular modelling based on a drug's pharmacophore.

• The study of how a drug interacts with its target binding site at the molecular level.

• The study of which functional groups are important in binding a drug to its target binding site and the identification of a pharmacophore.

Which of the following statements best describes pharmacokinetics?

• The study of how drugs reach their target in the body and how the levels of a drug in the blood are affected by various factors.

• The study of how drugs can be designed using molecular modelling based on a drug's pharmacophore.

• The study of how a drug interacts with its target binding site at the molecular level.

• The study of which functional groups are important in binding a drug to its target binding site and the identification of a pharmacophore.

Which of the following characteristics is detrimental to oral activity?

• stability to digestive enzymes

• susceptibility to metabolic enzymes

• stability to stomach acids

• solubility in both aqueous and fatty environments

Some orally active drugs do not obey the rule of five. For example, some drugs with molecular weights greater than 500 are found to be orally active. Which of the following mechanisms is the most likely reason for this?

• transport by transport protein

• passage through pores between the cells of the gut wall

• pinocytosis

• ion channels