A 45-year-old male is prescribed metformin for type 2 diabetes. Metformin works primarily by:

Correct Answer: B

Rationale: The correct answer is B: Improving insulin sensitivity in peripheral tissues. Metformin enhances the response of peripheral tissues to insulin, allowing for better utilization of glucose, reducing blood sugar levels. This mechanism helps to decrease insulin resistance, a key feature in type 2 diabetes. Other choices are incorrect because metformin does not directly increase insulin secretion from the pancreas (choice A), inhibit glucose absorption in the intestine (choice C), or increase the excretion of glucose in the urine (choice D). These mechanisms do not align with how metformin primarily works to improve glucose control in type 2 diabetes.

Correct Answer: A

Rationale: The correct answer is A: Cough and throat irritation. Albuterol is a bronchodilator commonly used to treat asthma and COPD. The mechanism of action of albuterol can lead to irritation of the throat and trigger coughing as a common adverse effect. This is due to the stimulation of beta-2 adrenergic receptors in the airways, causing relaxation of the smooth muscles but also potentially irritating the throat lining. Choices B, C, and D are incorrect because constipation, hypertension, and increased urination are not typically associated with albuterol inhalation therapy.

Correct Answer: B

Rationale: The correct answer is B: Sedation. Opioid analgesics commonly cause sedation due to their central nervous system depressant effects. They act on opioid receptors in the brain, leading to drowsiness and sedation. Diarrhea (A) is more commonly associated with opioid-induced constipation. Hypertension (C) is not a common adverse effect of opioids; they are more likely to cause hypotension. Hypokalemia (D) is not directly linked to opioid use. Sedation is the most prevalent adverse effect of opioids, making it the correct choice here.

Correct Answer: B

Rationale: The correct answer is B because ACE inhibitors work by inhibiting the conversion of angiotensin I to angiotensin II. Angiotensin II is a potent vasoconstrictor and also stimulates the release of aldosterone, leading to increased blood pressure. By blocking this conversion, ACE inhibitors help dilate blood vessels and reduce blood pressure. A: Blocking calcium channels is the mechanism of action of calcium channel blockers, not ACE inhibitors. C: Inhibiting aldosterone is the mechanism of action of aldosterone receptor antagonists, not ACE inhibitors. D: Increasing bradykinin levels is a side effect of ACE inhibitors, but not their primary mechanism of action.

Correct Answer: A

Rationale: The correct answer is A: Inhibiting sodium reabsorption in the kidneys. Hydrochlorothiazide is a thiazide diuretic that works by inhibiting the sodium-chloride symporter in the distal convoluted tubule of the kidneys, leading to increased excretion of sodium and water. This results in decreased blood volume and subsequently lowers blood pressure. Explanation of incorrect choices: B: Increasing sodium retention in the kidneys - This is the opposite effect of what hydrochlorothiazide does. C: Blocking calcium channels in the blood vessels - This is the mechanism of action for calcium channel blockers, not thiazide diuretics. D: Inhibiting ACE in the lungs - This is the mechanism of action for ACE inhibitors, not thiazide diuretics.