A 50-year-old man who has been taking phenobarbital for 1 week is found very lethargic and unable to walk after eating out for dinner. His wife states that he has no other prescriptions and that he did not take an overdose—the correct number of pills is in the bottle. The nurse suspects that which of the following may have happened?

Correct Answer: B

Rationale: The correct answer is B: He drank a glass of wine. Phenobarbital is a central nervous system depressant, and when combined with alcohol, it can enhance the sedative effects, leading to extreme lethargy and impaired motor skills. This interaction can be dangerous and life-threatening. Incorrect choices: A: Taking a multivitamin would not cause such severe symptoms when combined with phenobarbital. C: Aspirin does not typically interact in a significant way with phenobarbital to cause extreme lethargy and inability to walk. D: Developing an allergy to the drug would result in different symptoms, such as rash, swelling, or difficulty breathing, rather than extreme lethargy and impaired motor skills.

Correct Answer: C

Rationale: Rationale: 1. Patient C has coronary heart disease, indicating a higher risk of cardiovascular events. 2. The LDL level of 165 mg/dL is above the recommended target for patients with coronary heart disease. 3. Lowering cholesterol levels in patients with existing heart disease is crucial to reduce the risk of further complications. Summary: A: LDL level is within the recommended range for patients with coronary heart disease. B: LDL level is high, but the absence of coronary heart disease makes this patient less of a priority. D: Although the LDL level is optimal, having coronary heart disease takes precedence over the number of risk factors.

Correct Answer: B

Rationale: The correct answer is B: Increased activity tolerance. Iron supplements help increase red blood cell production, improving oxygen delivery to tissues and reducing fatigue. Increased activity tolerance is a common therapeutic response to iron supplementation. Decreased weight (A) is not a direct therapeutic response to iron supplementation. Decreased palpitations (C) may improve with increased iron levels, but it is not the primary expected outcome. Increased appetite (D) is not a typical response to iron supplementation and may not be directly related to improved anemia symptoms.

Correct Answer: C

Rationale: Systemic clearance (CLs) is related to the volume of distribution, half-life, and elimination rate constant. CLs represents the efficiency of elimination of a drug from the body and is calculated as the rate of drug elimination divided by the plasma concentration. The volume of distribution influences the initial concentration of the drug in the body, half-life determines the time taken for the drug concentration to decrease by half, and the elimination rate constant reflects the rate at which the drug is removed from the body. Therefore, these parameters directly impact systemic clearance. Choices A, B, and D do not encompass all the essential factors that contribute to systemic clearance, making them incorrect options.

Correct Answer: B

Rationale: The correct answer is B: Lidocaine. Lidocaine is an acetanilide derivative because it contains an acetanilide group in its chemical structure, making it a member of this specific chemical class of local anesthetics. Tetracaine is an ester derivative, not an acetanilide derivative. Cocaine is a tropane alkaloid derivative. Procaine is an ester derivative, not an acetanilide derivative. Therefore, based on the chemical structure and classification of local anesthetics, lidocaine is the only correct option.