Pharmacy Technician Certification Board Practice Exam

Which antihistamine is considered non-drowsy compared to others in its class?

1. Phenergan

2. Hydroxyzine

3. Meclizine

4. Loratadine

The correct answer is: Loratadine

Loratadine is considered a non-drowsy antihistamine because it is a second-generation antihistamine. This class of drugs is designed to selectively block peripheral histamine H1 receptors, which helps alleviate allergy symptoms such as sneezing, runny nose, and itchy eyes, while causing less sedation. Contrastingly, first-generation antihistamines, such as Phenergan (promethazine) and hydroxyzine, often cause significant drowsiness since they can cross the blood-brain barrier and have effects on the central nervous system. Meclizine, while used for motion sickness, is another first-generation antihistamine that can also lead to sedation. Loratadine's formulation allows it to be less sedating, making it a suitable choice for individuals who need to manage their allergy symptoms without the side effect of drowsiness. This non-drowsy characteristic is why loratadine stands out among the choices provided.