What are considered the ‘Big Three’ properties of an ideal drug? (Select all that apply)

Choice A reason: Synthesis of more receptor sites (upregulation) typically occurs with receptor antagonists, not agonists, as the body compensates for blocked receptors. This would increase drug sensitivity, not decrease effectiveness. For most medications, continuous exposure leads to desensitization, not receptor proliferation, making this choice incorrect for explaining tolerance.

Choice B reason: Decreased receptor selectivity implies a drug binding to unintended receptors, causing varied effects, not reduced efficacy. Tolerance results from receptor desensitization, not altered selectivity. This mechanism doesn’t explain the patient’s “immunity” to the drug’s therapeutic effects, making this choice scientifically inaccurate for the scenario.

Choice C reason: Desensitization occurs when continuous drug exposure reduces receptor responsiveness, leading to tolerance. For example, opioid receptors downregulate or internalize with prolonged agonist exposure, decreasing drug efficacy. This explains the patient’s perception of “immunity” as the drug’s effect diminishes over time, making this the correct choice.

Choice D reason: The body does not produce antagonists to compete with drugs for receptor sites. Tolerance arises from receptor desensitization or metabolic changes (e.g., enzyme induction), not endogenous antagonist production. This mechanism is not a recognized pharmacological process for reduced drug effectiveness, making this choice incorrect.

Choice A reason: Enteral (oral) administration typically has slower absorption than intravenous routes due to first-pass metabolism in the liver and variable gastric emptying. While effective for many drugs, it’s not faster than parenteral routes, making this choice incorrect for describing the primary advantage of enteral administration.

Choice B reason: Some enteral drugs are inactivated by digestive enzymes or liver metabolism (first-pass effect), not prevented. Special formulations (e.g., enteric-coated) may protect drugs, but this isn’t a general advantage of the enteral route, which often faces enzymatic degradation, making this choice inaccurate.

Choice C reason: Enteral administration does not offer superior control of serum drug levels compared to intravenous routes, which provide precise dosing and immediate bioavailability. Oral drugs face variable absorption and first-pass metabolism, leading to less predictable levels, making this choice incorrect for enteral benefits.

Choice D reason: Enteral administration is safer (avoids injection risks like infection), less expensive (no need for sterile equipment), and more convenient (self-administered at home). These advantages make it preferable for many drugs, aligning with patient compliance and cost-effectiveness, making this the correct choice for the nurse’s response.