Loratadine is classified as which type of antihistamine?

• A. Non-sedating second-generation antihistamine
• B. First-generation H1 blocker
• C. Beta-blocker
• D. H2 blocker

Answer: (A)

Loratadine is a non-sedating second-generation antihistamine because it blocks peripheral H1 receptors with little effect on the brain. Its chemical properties limit crossing of the blood–brain barrier (often due to P-glycoprotein transport and lower CNS penetration), so it provides allergy relief without the drowsiness typical of older, first-generation antihistamines. It’s designed to minimize central nervous system effects and anticholinergic activity, while still countering histamine-driven symptoms. It is not a beta-blocker and not an H2 blocker, which is why these options don’t fit. The classification as a second-generation antihistamine reflects both its peripheral action and its minimal sedation.