Which of the following drugs most likely interacted with metoclopramide, thus triggering the adverse effects reported by the patient?

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: 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.

Correct Answer: D

Rationale: The correct answer is D: Fentanyl. Fentanyl is a potent synthetic opioid commonly used for severe pain management. The patient most likely took Fentanyl due to its high potency, fast onset of action, and effectiveness in managing severe pain. Buprenorphine (A) is a partial opioid agonist used for opioid addiction treatment, not typically for severe pain. Morphine (B) is a strong opioid but less potent than Fentanyl and not commonly used for severe pain management. Pentazocine (C) is a mixed opioid agonist-antagonist and not as potent as Fentanyl for severe pain relief.