Diphenhydramine

Question 1

Diphenhydramine Trade Name?

Answer 1

Benadryl

Question 2

Diphenhydramine Classification?

Answer 2

Antihistimine

Question 3

Diphenhydramine Mechanism?

Answer 3

acts as an INVERSE AGONIST at the H1 receptor, thereby reversing the effects of histamine on capillaries, reducing allergic reaction symptoms.

Question 4

Diphenhydramine Indications?

Answer 4

• Allergy/Anaphylaxis
• Dystonia

Question 5

Diphenhydramine Contraindications?

Answer 5

None in an emergency setting

Question 6

Diphenhydramine Side Effects/Precautions?

Answer 6

• Dizziness
• Drowsiness
• Confusion
• Dry Mouth
• Hypotension
• Nausea/Vomiting

Question 7

Diphenhydramine Adult Dose?

Answer 7

25-50 mg
*statpearls

Question 8

Diphenhydramine Pediatric Dose?

Answer 8

2 to 11 years: 1-2mg/kg PO/IM/IV
*statpearls

Question 9

Diphenhydramine Onset of Action?

Answer 9

10-15 min (IV)
15-30 min (PO)
20-30 min (IM)

Question 10

Diphenhydramine Duration of Action?

Answer 10

6-8 hours

Question 11

Diphenhydramine Max Dose Adult/Pediatric?

Answer 11

Adult: 400mg/day (IV/IO) 300mg/day (PO)
Ped: 2 to 5 years: max 37.5 mg/day
6 to 11 years: max 150 mg/day
12 years and older: use adult dosing

Question 12

Diphenhydramine Routes of Administration?

Answer 12

IV/IO/PO/IM

Question 13

Diphenhydramine How Supplied?

Answer 13

10mg/ml and 50mg/ml vials; 25mg and 50mg tablets