What is a common adverse effect of albuterol inhalation therapy?

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 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.

Correct Answer: B

Rationale: The correct answer is B: Non-competitive antagonist. This is because a non-competitive antagonist binds irreversibly to a different site on the receptor compared to the agonist (norepinephrine in this case) and prevents its activation, leading to a decrease in response. In the graph, the presence of Drug X shifts the concentration-response curve of norepinephrine downward without affecting the maximum response, indicating non-competitive antagonism. A: Silent antagonists do not affect the agonist's binding or activity on the receptor. C: Competitive antagonists compete with the agonist for the same binding site on the receptor, affecting potency but not the maximum response. D: Chemical antagonist is a broad term for any antagonist that binds to the agonist or receptor to prevent activation but does not specifically describe the mechanism like non-competitive antagonism does.

Correct Answer: A

Rationale: The correct answer is A: Constriction of cerebral vessels. Ergotamine is known to constrict cerebral blood vessels, which helps in preventing migraine attacks by reducing the dilation of these vessels that occurs during a migraine. This constriction helps to decrease the pulsatile headache pain associated with migraines. B: Extravasation of plasma into perivascular space is incorrect because it does not contribute to the therapeutic effect of ergotamine in treating migraines. C: Prostaglandin release from vascular endothelium is incorrect because ergotamine works by vasoconstriction rather than affecting prostaglandin release. D: Platelet aggregation in the cerebral vascular bed is incorrect because ergotamine does not target platelet aggregation as a mechanism of action in treating migraines.