What is the primary function of antihistamines?

• A. Promote inflammation
• B. Block the release of histamines
• C. Increase sensitivity to allergens
• D. Regulate blood pressure

Answer: (B)

Antihistamines primarily function by blocking the action of histamines, which are substances in the body that are involved in allergic responses. When allergens are encountered, the body releases histamines that bind to specific receptors, leading to symptoms such as itching, swelling, and mucus production. By blocking these receptors, antihistamines help to alleviate these allergic symptoms and provide relief from conditions such as hay fever, allergies, and colds. This action is crucial in managing allergic reactions and providing symptomatic treatment for patients.

The other choices relate to different physiological processes that do not accurately reflect the role and mechanism of antihistamines. Promoting inflammation or increasing sensitivity to allergens would exacerbate allergic responses rather than mitigate them. Regulating blood pressure pertains to a different class of medications entirely, unrelated to the primary functions of antihistamines.