Antihistamines

Question 1

Diphenhydramine - brand name

Answer 1

zyrtec

Question 2

diphenhydramine - Indication

Answer 2

allergic rhinitis; allergic reaction (hives/itching)

Question 3

diphenhydramine - MOA

Answer 3

competes with H-1 for receptor site; blocks H-1 release; poor selectivity -> CNS + anticholinergic effects

Question 4

Diphenhydramine - contraindication

Answer 4

hypersensitivity

Question 5

diphenhydramine - common reaction

Answer 5

sedation; drowsiness; headache; dry mouth; children = more excitation

Question 6

diphenhydramine - rare, but serious

Answer 6

cognitive impairment
urinary retention
blurred vision (with consistent use, elderly more susceptible)

Question 7

Diphenhydramine - counseling

Answer 7

NO DRIVING
NO ALCOHOL
caution for the elderly

Question 8

diphenhydramine - alternatives

Answer 8

meclizine (Antivert, Bonine, Dramamine): N/V + motion sickness
hydroxyzine (Atarax, Vistaril): for itching or sedation

Question 9

Cetirizine - brand name

Answer 9

Zyrtec

Question 10

Cetirizine - indication

Answer 10

allergic rhinitis, itching/hives (urticaria)
intranasal -> local relief

Question 11

cetirizine - MOA

Answer 11

competes with H-1 for receptor site; blocks H-1 release; poor selectivity -> CNS + anticholinergic effects
BUT more selective for peripheral receptors

Question 12

cetirizine - contraindication

Answer 12

hypersensitivity

Question 13

cetirizine - common reaction

Answer 13

drowsiness
headache
azelastine (intranasal): bitter taste, epistaxis (nose bleed)

Question 14

cetirizine - counseling

Answer 14

Avoid activities with mental alertness (unless you know how you react)
other OTC if this doesnt work

Question 15

cetirizine - alternatives

Answer 15

Fexofenadine (Allegra)
Levocetirizine (Xyzel)
Azelastine (Astepro, Astelin)