A drug with which of the following molecular mechanisms of action would be appropriate for this patient?

Correct Answer: C

Rationale: The correct answer is C: Inhibition of serotonin transporter. This mechanism of action would be appropriate for this patient as it increases serotonin levels in the synaptic cleft, which can help alleviate symptoms of depression. Monoamine oxidase A inhibition (Choice A) is used for atypical depression. Serotonergic receptor blockade (Choice B) can worsen depression symptoms. Blockade of β receptors (Choice D) is used for conditions like hypertension, not depression. In summary, choice C is the most suitable for treating depression by increasing serotonin levels, while the other choices are either ineffective or potentially harmful for this condition.

Correct Answer: A

Rationale: The correct answer is A: Amitriptyline. Metoclopramide interacts with amitriptyline by inhibiting its metabolism, leading to increased levels of amitriptyline in the body. This can result in adverse effects such as sedation, confusion, and potential serotonin syndrome. Explanation: 1. Metoclopramide is known to inhibit CYP2D6 enzyme, which is responsible for metabolizing amitriptyline. 2. Increased amitriptyline levels can lead to enhanced sedative effects and central nervous system depression. 3. The combination can also increase the risk of serotonin syndrome due to the additive serotonergic effects of both drugs. Summary: B: Lithium - Lithium does not have a significant metabolic interaction with metoclopramide. C: Zolpidem - Zolpidem is primarily metabolized by different enzymes and does not interact significantly with metoclopramide. D: Paroxetine - Although both

Correct Answer: C

Rationale: The correct answer is C: Insomnia. During the first days of lithium therapy, individuals are more likely to experience insomnia due to the stimulating effects of lithium on the central nervous system. This can disrupt sleep patterns and cause difficulty falling or staying asleep. Choice A (Constipation) is less likely to occur as lithium is not known to have a significant impact on gastrointestinal motility. Choice B (Weight loss) is also less likely as weight gain is a more common side effect of lithium therapy. Choice D (Hypertension) is not typically seen in the initial days of lithium therapy, as lithium is more commonly associated with long-term kidney-related issues leading to hypertension.

Correct Answer: B

Rationale: The correct answer is B: Norepinephrine. Norepinephrine is a neurotransmitter and a medication that can increase blood pressure by constricting blood vessels. Atomoxetine (A) is used to treat ADHD and does not typically cause high blood pressure. Phenylephrine (C) is a decongestant that can raise blood pressure temporarily. Guanfacine (D) is a medication used to lower blood pressure, so it is unlikely to be the cause of the patient's high blood pressure.

Correct Answer: D

Rationale: The correct answer is D, the lateral hypothalamus. Amphetamines are known to suppress appetite by affecting the lateral hypothalamus, a region of the brain responsible for regulating hunger and feeding behavior. Stimulation of the lateral hypothalamus can lead to reduced food intake. Choices A, B, and C are not directly involved in appetite regulation and do not play a significant role in the anorectic action of amphetamines.