Which type of drug is used for mild allergic reactions and can cause side effects such as drowsiness and xerostomia?

Antihistamines are specifically designed to alleviate symptoms associated with allergic reactions by blocking the action of histamine, a substance in the body that causes allergic symptoms. In the case of mild allergic reactions, these medications are effective at reducing symptoms such as itching, sneezing, and runny nose.

One of the common side effects associated with antihistamines is drowsiness, which occurs because many first-generation antihistamines can cross the blood-brain barrier and have sedative effects. Additionally, antihistamines can lead to xerostomia, or dry mouth, due to their anticholinergic properties, which inhibit saliva production.

This profile makes antihistamines the appropriate choice for treating mild allergic reactions while also being aware of their potential side effects, enhancing understanding of their use in patient care.