A 60-year-old male with hypertension is prescribed losartan. Losartan works by:

Correct Answer: A

Rationale: The correct answer is A: Blocking angiotensin II receptors. Losartan is an angiotensin II receptor blocker (ARB) that works by specifically blocking the angiotensin II receptor type 1 (AT1) receptors. Angiotensin II is a potent vasoconstrictor, and by blocking its action at the receptor level, losartan helps dilate blood vessels and reduce blood pressure. This mechanism is specific to ARBs and distinguishes them from other classes of antihypertensive medications. Choice B: Inhibiting the reuptake of norepinephrine is incorrect as this mechanism is associated with drugs like tricyclic antidepressants and not losartan. Choice C: Blocking calcium channels in the blood vessels is incorrect as this mechanism is associated with calcium channel blockers like amlodipine, not losartan. Choice D: Inhibiting aldosterone secretion is incorrect as this mechanism is associated with drugs like

Correct Answer: A

Rationale: The correct answer is A: Constipation. Opioid medications slow down gut motility, leading to constipation. Opioids bind to receptors in the gastrointestinal tract, reducing the movement of food and stool. This commonly results in constipation. Choices B, C, and D are incorrect because nausea and vomiting, increased appetite, and dehydration are not common side effects specifically associated with opioid medications.

Correct Answer: B

Rationale: Step-by-step rationale: 1. Ipratropium bromide is a bronchodilator commonly used in COPD. 2. It works by relaxing muscles in the airways to improve breathing. 3. Asthma is typically treated with other bronchodilators like albuterol. 4. Hypertension is managed with antihypertensive medications. 5. Arrhythmia is treated with antiarrhythmic drugs. In summary, ipratropium bromide is specifically indicated for COPD due to its mechanism of action on the airways, making choices A, C, and D incorrect for this question.

Correct Answer: A

Rationale: The correct answer is A because alendronate is a bisphosphonate that inhibits bone resorption by osteoclasts. Osteoclasts are responsible for breaking down bone tissue, and alendronate helps to reduce bone loss by suppressing their activity. This leads to an increase in bone mineral density and strength. Choices B, C, and D are incorrect because alendronate does not promote bone formation by osteoblasts, increase calcium absorption in the intestines, or inhibit the synthesis of collagen. The primary mechanism of action of alendronate is through the inhibition of osteoclast-mediated bone resorption.

Correct Answer: B

Rationale: The correct answer is B: Prothrombin time (PT) and international normalized ratio (INR). PT measures the time it takes for blood to clot, and INR is a standardized way to interpret PT results. Warfarin affects the clotting process, so monitoring PT/INR helps assess its therapeutic effect. CBC (A) checks blood cell counts, not specific to warfarin. Serum creatinine (C) assesses kidney function, not related to warfarin. Liver function tests (D) evaluate liver health, not directly related to warfarin's anticoagulant effect. PT/INR is the key test for monitoring warfarin therapy.