An antihistamine counters the effects of histamine. which of the following is an effect of histamine?
a. increased blood flow brings more warmth to the area, causing a local "fever" that white blood cells and suppresses microbes.
b. capillary dilation increases blood flow and causes surface redness.
c. increased blood flow brings more white blood cells to the site of injury or invasion.
d. increased blood flow and permeability increase the fluids in the tissues, causing them to swell.

The correct answer will be option-D

Explanation:

Histamines are the nitrogenous compounds which play an important role in providing immunity.

The histamines are produced by the mast cells and basophils which when produced act in the body by causing dilation of the blood capillaries (vasodilation) and then increasing permeability causing the tissue to swell. This produces an allergic reaction.

Antihistamines act by suppressing the binding of the histamine to their receptors thus suppresses the allergic reaction.

Thus, option-D is the correct answer.

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helicase, i think thats it