Histamin causes:
A
Vasodilatation
B
Bradycardia
C
Hypertension
D
Vasoconstriction
Correct Answer: Vasodilatation
Histamine - a chemical found in some of the body's cells - causes many of the symptoms of allergies, such as a runny nose or sneezing. When a person is allergic to a particular substance, such as a food or dust, the immune system mistakenly believes that this usually harmless substance is actually harmful to the body.