Hydroxyzine hydrochloride is a first-generation antihistamine commonly used for the treatment of itchiness (pruritus), anxiety, insomnia, and nausea. As an H1 receptor antagonist, it works by blocking the effects of histamine, a chemical responsible for allergic reactions, making it effective in relieving itching, hives, and other allergic skin conditions. Unlike newer antihistamines, hydroxyzine has sedative properties, which contribute to its ability to calm the nervous system and promote relaxation. This makes it a useful option for managing anxiety disorders and providing short-term relief of nervous tension. Additionally, its sedative effect is beneficial for individuals struggling with insomnia, as it helps induce sleep without the risks associated with stronger sedatives or benzodiazepines.

Beyond its role in allergy and anxiety treatment, hydroxyzine is also prescribed for nausea and motion sickness, as it has antiemetic properties that help reduce vomiting and dizziness. It is sometimes used as a preoperative sedative to calm patients before surgery and enhance the effects of anesthesia. Despite its benefits, hydroxyzine may cause side effects such as drowsiness, dry mouth, dizziness, and blurred vision, which should be considered when performing tasks that require alertness. Due to its central nervous system depressant effects, it should be used cautiously in elderly patients or those taking other sedative medications. However, when used appropriately under medical supervision, hydroxyzine remains a versatile and effective medication for treating a wide range of conditions, from allergic reactions to anxiety-related disorders.