A patient tells a nurse that antihistamines help relieve cold symptoms and wants to know why they are not recommended or prescribed for this purpose. The nurse tells the patient that antihistamines provide relief from some cold symptoms by:

Question

Quizplus · Accepted Answer

Histamine does not mediate cold symptoms, so antihistamines do not provide relief through H₁ blockade. Their anticholinergic effects at muscarinic receptor sites can moderately reduce rhinorrhea, so some patients may experience some relief of this symptom. H₁-receptor sites do not play a role in cold symptoms. H₂-receptor sites do not play a role in cold symptoms. Sedative side effects do not alleviate cold symptoms.

A Patient Tells a Nurse That Antihistamines Help Relieve Cold