Antihistamine

Question 1

H1

Answer 1

• Vasodilation
  
  • Increased capillary permeability
  • Bronchoconstriction
  • CNS effects: seizure suppression, regulation of energy and endocrine homeostasis
  • Other effects: itching and pain, mucus secretion

Question 2

H2

Answer 2

• Secretion of gastric acid

Question 3

Histamine is synthesized and stored in two types of cells:

Answer 3

• Mast cells and basophils

Question 4

Allergic release (3 phases)

Answer 4

• Phase 1: formation of IgE
  
  • Phase2 : binding of IgE to mast cell
  • Phase 3: release of histamine

Question 5

1st generation H1 antagonist

Answer 5

highly sedative

Question 6

2nd generation H1 antagonist

Answer 6

○ Cross the BBB poorly
○ Low affinity for H1 receptors of the CNS
○ Fexofendaine (Allegra), avoid fruit juice