Histamine and antihistamines

Question 1

1st vs 2nd generation H1 antihistamine?

Answer 1

Question 2

Answer 2

Question 3

What are histaminergic neurons responsible for?

Answer 3

Question 4

What effects do antihistamines have on these locations?

Answer 4

Question 5

How do first generation antihistamines differ molecularly to 2nd generation?

Answer 5

Start to deviate from the original structures which are very similar to histamine, this means that there are less side effects.

Question 6

Type 1 vs 2 vs 3 vs 4 hypersensitivity explained.

Answer 6

Question 7

What is anaphylactic shock?

Primary vs secondary treatment?

Answer 7

Question 8

MOA 1st generation antihistamines?
What are they used for?

Blood brain barrier?

Answer 8

Competitive reversible antagonists.

Antiemetic effect from binding to M1 and H1 receptors in vestibular apparatus.

• Reduce inflammation, itch, used for hayfever etc, sedative for insomnia, antiemetic so can be used for pregnancy/radiation/chemo induced vomiting and motionsickness.

Question 9

Why 1st generation antihistamines be used for the common cold?

What are some of the side effects?

Answer 9

Reduce tear formation, saliva, urinary output, heart (increased heart rate), ‘brain fog’.

• Can also cause hypotension, flushing etc as they act on the alpha 1 receptor.

Question 10

MOA of 2nd/3rd generation antihistamines?

how do they compare to 1st generation?

Answer 10

Question 11

Metabolism of 1st generation antihistamines?

What are they affected by?

Answer 11

Question 12

What does anticholinergic mean?

Answer 12

associated with activation of the parasympathetic nervous system

Question 13

metabolism of 2nd class antihistamines.

Answer 13

Question 14

antihistamines in elderly?

Answer 14

Question 15

Antihistamine in elderly?

Answer 15

Question 16

Antihistamine in children?

Answer 16

Question 17

Answer 17