Which second-generation antihistamine is associated with sedation?

Which second-generation antihistamine is associated with sedation?

• A. Loratadine
• B. Fexofenadine
• C. Desloratadine
• D. Cetirizine

Answer: (D)

Sedation risk is the point being tested. Of the second-generation antihistamines listed, this one has the highest likelihood of causing drowsiness. That happens because it crosses into the central nervous system more readily than the others, leading to some central H1 receptor blockade and sleepiness in some people. The other medications in this group are designed to stay more peripherally focused, with far less CNS penetration, so they’re much less likely to cause sedation. Still, at higher doses or in sensitive individuals, even this option can cause sleepiness, so use caution if you need to drive or perform tasks requiring alertness.

Sedation risk is the point being tested. Of the second-generation antihistamines listed, this one has the highest likelihood of causing drowsiness. That happens because it crosses into the central nervous system more readily than the others, leading to some central H1 receptor blockade and sleepiness in some people. The other medications in this group are designed to stay more peripherally focused, with far less CNS penetration, so they’re much less likely to cause sedation. Still, at higher doses or in sensitive individuals, even this option can cause sleepiness, so use caution if you need to drive or perform tasks requiring alertness.