How does montelukast (Singulair), a leukotriene blocker, work in the treatment of asthma?

Choice A reason: This is not a physiological response to hydralazine. Cool extremities are a sign of poor peripheral perfusion, which can be caused by vasoconstriction, not vasodilation.

Choice B reason: This is not a physiological response to hydralazine. Increased urinary output is a sign of diuresis, which can be caused by diuretic medications, not vasodilators.

Choice C reason: This is not a physiological response to hydralazine. Pale skin is a sign of reduced blood flow to the skin, which can be caused by vasoconstriction, not vasodilation.

Choice D reason: This is a physiological response to hydralazine. Reflex tachycardia is a compensatory mechanism that occurs when the blood pressure drops due to vasodilation. The heart rate increases to maintain the cardiac output and perfusion pressure.

Choice A reason: Infection in the blood is not empyema. It is sepsis, which is a life-threatening condition that occurs when the body's response to infection causes tissue damage, organ failure, or death.

Choice B reason: Infection in the pleural space is empyema. It is a collection of pus in the space between the lungs and the chest wall, usually caused by a bacterial infection that spreads from the lungs or the chest cavity.

Choice C reason: Exudative bronchitis is not empyema. It is a type of bronchitis that involves inflammation and excess mucus production in the bronchi, the airways that carry air to the lungs.

Choice D reason: Infection localized in the lung is not empyema. It is pneumonia, which is an inflammation of the lung tissue, usually caused by a viral or bacterial infection that affects the air sacs or the interstitial tissue.