A 45-year-old male with depression is prescribed sertraline. Sertraline works by:

Correct Answer: A

Rationale: The correct answer is A: Increasing serotonin levels in the brain by inhibiting its reuptake. Sertraline is a selective serotonin reuptake inhibitor (SSRI), which means it inhibits the reuptake of serotonin in the brain, leading to increased levels of serotonin available for neurotransmission. This helps alleviate symptoms of depression by enhancing serotonin signaling. Choices B, C, and D are incorrect because sertraline specifically targets serotonin reuptake, not norepinephrine, dopamine, monoamine oxidase, or acetylcholine.

Correct Answer: A

Rationale: The correct answer is A: Oxybutynin. Oxybutynin is an anticholinergic medication that helps relax the bladder muscles, reducing urinary frequency and urgency in overactive bladder. Furosemide (B) is a diuretic used to treat fluid retention, not overactive bladder. Amlodipine (C) is a calcium channel blocker used to treat high blood pressure, not overactive bladder. Metformin (D) is an antidiabetic drug used for managing type 2 diabetes, not overactive bladder. Oxybutynin is the most appropriate choice for treating overactive bladder due to its muscle relaxant effects on the bladder.

Correct Answer: C

Rationale: The correct answer is C: Blocking beta-1 adrenergic receptors in the heart. Atenolol is a beta-blocker that specifically targets beta-1 adrenergic receptors in the heart, leading to decreased heart rate and contractility, thereby reducing blood pressure. Choice A is incorrect as blocking calcium channels is the mechanism of action for calcium channel blockers. Choice B is incorrect as angiotensin-converting enzyme inhibitors (ACE inhibitors) inhibit the enzyme that produces angiotensin II. Choice D is incorrect as diuretics are medications that increase the excretion of sodium in the kidneys.

Correct Answer: B

Rationale: The correct answer is B: Inhibiting the conversion of angiotensin I to angiotensin II. Lisinopril is an ACE inhibitor, which blocks the enzyme responsible for converting angiotensin I to angiotensin II. Angiotensin II is a potent vasoconstrictor, so by inhibiting its production, lisinopril helps dilate blood vessels, lowering blood pressure. Choice A is incorrect because calcium channel blockers work differently. Choice C is incorrect because aldosterone release is not directly affected by lisinopril. Choice D is incorrect because beta-blockers target a different pathway in the heart.

Correct Answer: B

Rationale: Step 1: SSRIs are a class of antidepressants that work by increasing serotonin levels in the brain. Step 2: Fluoxetine is an SSRI commonly used to treat depression and other mental health conditions. Step 3: Sertraline, citalopram, and lorazepam are not SSRIs but belong to other classes of medications. Summary: Sertraline, citalopram, and lorazepam are incorrect choices as they do not belong to the SSRI class like fluoxetine does.