Which of the following drugs most likely caused the symptom reported by the patient?

Correct Answer: D

Rationale: The correct answer is D: Chlorpromazine. The patient reported symptoms are likely extrapyramidal side effects, such as tremors, muscle rigidity, and akathisia, which are common with typical antipsychotics like chlorpromazine. Lithium (A) is used for bipolar disorder, not associated with these side effects. Amitriptyline (B) is a tricyclic antidepressant, known for sedation and anticholinergic effects. Fluoxetine (C) is a selective serotonin reuptake inhibitor, not known for causing extrapyramidal symptoms. Therefore, based on the symptoms described, chlorpromazine is the most likely culprit.

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.

Correct Answer: C

Rationale: The correct answer is C: Guanfacine. Guanfacine is commonly prescribed for children with irritability and self-injurious behavior due to its effectiveness in treating symptoms of ADHD and disruptive behavior disorders. It helps regulate impulse control and reduce aggression. Dextroamphetamine and Methylphenidate (Choices A and B) are stimulant medications primarily used for ADHD but may not directly address irritability and self-injurious behavior. Bupropion (Choice D) is an antidepressant and not typically the first choice for managing irritability and self-injurious behavior in children.