Some drugs used to treat allergies may produce drowsiness if they ____.

Question

Some drugs used to treat allergies may produce drowsiness if they ____.​

Quizplus · Accepted Answer

Drugs that block histamine receptors are known as antihistamines and are commonly used to treat allergies. Some antihistamines, such as diphenhydramine, can cross the blood-brain barrier and bind to histamine receptors in the brain, causing drowsiness. This is why some antihistamines are marketed as sleep aids. Stimulating acetylcholine, decreasing adenosine, or blocking GABA are not mechanisms of action for allergy medications and are not known to cause drowsiness in this context.

Some Drugs Used to Treat Allergies May Produce Drowsiness If