Diphenhydramine Flashcards
1
Q
Benadryl
Class
A
- Antihistamine
- Anticholinergic
2
Q
Benadryl
Mechanism of action
A
- Blocks cellular histamine receptors
- Decrease vasodilation
- Reduce motion sickness
- Reverse extrapyramidal reactions
3
Q
Benadryl
Indications
A
- Symptomatic relief of allergies, allergic reactions & anaphylaxis
- Acute dystonic reactions (phenothiazines)
- Motion sickness and hayfever
- Blood administration reactions
4
Q
Benadryl
Contraindications
A
- Asthma
- Glaucoma
- Pregnancy
- Infants
- PT taking MAOI’s (monamine oxidase inhibitors)
- HTN
5
Q
Benadryl
Adverse reactions
A
- Sedation
- Hypotension
- SZ
- Visual disturbances
- Paradoxical CNS excitation in children
- Palpitations and arrythmias
- Dry mouth and throat
6
Q
Benadryl
Drug interactions
A
- Potentiates ETOH and anticholinergics
- Inhibits corticosteroids
- MAOI’s may prolong anticholinergic effects
7
Q
Benadryl
Dosage and administration
A
-
Adult:
- 25-50mg IM, IV
-
Ped:
- 1-2 mg/kg slow IV or IM
- If given PO: 5mg/kg/24 hrs
8
Q
Benadryl
Duration of action
A
- Onset: 15-30 min
- Peak effect: 1 hr
- Duration: 3-12 hrs
9
Q
Benadryl
Special considerations
A
- Pregnancy: Cat B
- Not used in infants or in pregancy
- If used in anaphylaxis, will be used in conjuction with Epi & corticosteroids
