Allergies

Question 1

Background information for Antihistamines

Answer 1

Histamine is associated with symptoms of seasonal allergies

Question 2

Pharmacology of Antihistamines

Answer 2

Antihistamines antagonize H1 receptors, opposing the effects of histamine

Question 3

Indications of Antihistamines

Answer 3

• Allergies
• Insomnia
• Motion sickness

Question 4

Side effects of Antihistamines

Answer 4

• Drowsiness

Question 5

Drug interactions of Antihistamines

Answer 5

• Increased drowsiness when used with other drugs that suppress central nervous system activity

Question 6

Important note for Antihistamines

Answer 6

• First-generation antihistamines can cross the blood-brain barrier, antagonizing histamine receptors in the central nervous system and causing drowsiness
• Antihistamines typically cause sedation
• Second-generation antihistamines do not cross the blood-brain barrier and do not cause sedation