Antihistamines

Question 1

Name 1 st generation antihistamines?

Answer 1

1. Hydroxyzine
2. Chlorpheniramine
3. Diphenhydramine

Question 2

Name 2nd generation antihistamines?

Answer 2

1. Cetirizin (= metabolite of hydroxyzine)
2. Loratadine (didn´t work in any study, is not used anymore)
3. Terfenadine (cave: cardiac AE!)
4. Mizolastine

Question 3

Name 3rd generation of H1 antihistamines?

Answer 3

1. Levocetirizin
2. Desloratadine
3. Fexofenadine

Question 4

General info about cetirizine

Answer 4

-Halflife of cetirizin is 10-11 h
-It can inhibit formation of histamine induced wheal formation
-It gets metabolized in the liver and excreted with urine
CYP450 is involved

Question 5

When is cetrizine contraindicated?

Answer 5

1. Glaucoma
2. GI atony
3. Urinary retention states

Question 6

Name behavior-modifying tricyclic antidepressants that are also H1-R antagonists and have been used in the management of pruritic dogs & cats:

Answer 6

1. Amitriptylline
2. Clomipramine
3. Doxepin

Question 7

Amitriptylline, Clomipramine, Doxepin – name possible AE:

Answer 7

-Sedation
-Cardiac arhythmias
-Dry mouth
-urine retention
-Tears retention
-Diarrhea
-Vomiting
-Polydipsia
-aggression