Week 6: Allergy Medications Flashcards
1
Q
Diphenhydramine (Benadryl) indications
A
- allergic rhinitis
- hypersensitivity reactions
- urticaria and angioedema
- insomnia
- motion sickness antiemetic
2
Q
Diphenhydramine Drug Class
A
1st Generation Antihistamine
3
Q
Diphenhydramine MOA
A
- competes with histamine at the H1 receptor sites of GI, blood vessels, and respiratory tract
- prevent RESPONSES mediated by histamine (NOT histamine release)
4
Q
Diphenhydramine Cautions/ Contraindications
A
- crosses the blood-brain barrier (DON’T combine with CNS depressants)
- avoid in patients with glaucoma, BPH d/t anticholinergic effects
- avoid in infants, young child (CNS stimulation instead of depression), elderly (BEERS)
- Safe in pregnancy
- avoid in lactation (dries up milk production)
5
Q
1st Generation Antihistamines (Benadryl) ADRs
A
- sedation - dizziness - confusion - ataxia - urinary retention - paradoxical excitation - dry mouth - tremor - blurred vision - constipation (think anticholinergic effects and CNS effects)
***cross the blood-brain barrier***
6
Q
2nd Generation Antihistamines Examples
A
Cetirizine (Zyrtec) Loratadine Fexofenadine
7
Q
2nd Generation Antihistamine (Zyrtec/ Loratadine/ Fexofenadine) indications
A
- respiratory allergies - urticaria
8
Q
2nd Generation Antihistamine MOA (Zyrtec/ Loratadine/ Fexofenadine)
A
- antagonizes the effects of histamine at the peripheral H1 receptor sites in the GI tract, blood vessels, and repiratory tract
- DOESN’T cross the blood-brain barrier
- no anticholinergic effects (unlike 1st generation)
9
Q
2nd Generation Antihistamines - Cetirizine, Loratadine, Fexofenadine cautions/ contraindications
A
- safe in pregnancy and lactation
- may have some CNS effects and can cause drowsiness - not as much as with 1st gen.
- Cetirizine ok for 6mo+, fastest onset, least metabolized by CYP450
- Loratadine ok for > 2 year olds & BEST for lactation (think lact ok in loratadine); but NOOOO liver pts
- Fexofenadine ok for > 6 year olds
