NAPLEX (North American Pharmacist Licensure Examination) Practice Exam

What common side effect is associated with first generation antihistamines?

1. Nausea

2. Epistaxis

3. Sedation

4. Headache

The correct answer is: Sedation

Many first generation antihistamines, such as Benadryl and Chlor-Trimeton, have sedative properties which can cause drowsiness and fatigue. This side effect is more prominent in first generation antihistamines compared to second generation, which have less sedative effects. Nausea, epistaxis, and headache are not commonly associated with first generation antihistamines. Nausea is more commonly associated with antihistamines that are combined with decongestants. Epistaxis (nosebleeds) may occur in rare cases as a result of drying out of the nasal passages, but it is not a common side effect. Headaches are also not commonly associated with first generation antihistamines. It is important to note that different individuals may experience different side effects from medication, so it is always best to consult with a doctor or pharmacist if you have any concerns.