Group 7 - Diphenhydramine HCl (Benadryl)

Question 1

Diphenhydramine HCl (Benadryl)

Drug Class?

Answer 1

Diphenhydramine HCl (Benadryl)

Drug Class:

• Antihistamine
• Anticholinergic

Question 2

Diphenhydramine HCl (Benadryl)

Mechanism of Action (MOA)?

Answer 2

Diphenhydramine HCl (Benadryl)

MOA:

• Blocks cellular histamine receptors but does not prevent histamine release
• Decreased capillary permeability and decreased vasodilation

Question 3

Diphenhydramine HCl (Benadryl)

Indications?

Answer 3

Diphenhydramine HCl (Benadryl) Indications:

• Anaphylaxis (2^nd line)
• Phenothiazine reactions (extrapyramidal symptoms)
• Antiemetic

Question 4

Diphenhydramine HCl (Benadryl)

Contraindications?

Answer 4

Diphenhydramine HCl (Benadryl) Contraindications:

• Hypersensitivity
• Newborn or premature infants; nursing mothers
• Caution in patients with acute narrow angle glaucoma, asthma, hyperthyroidism

Question 5

Diphenhydramine HCl (Benadryl)

Adverse Reactions?

Answer 5

Diphenhydramine HCl (Benadryl) Adverse Reations:

• CV: hypotension, palpitations, arrhythmias, hemolytic anemia
• Resp: Anaphylaxis; thickening of bronchial secretions; chest tightness
• GI: urinary frequency or retention; vomiting
• CNS: sedation; seizures; visual disturbances
• Children: paradoxial CNS excitation; seizures; palpitations; thickening of bronchial secretions

Question 6

Diphenhydramine HCl (Benadryl)

Adult Dose?

Answer 6

Diphenhydramine HCl (Benadryl)

Adult Dose:

• Anaphylaxis: 25 - 50 mg slow IV push or deep IM
• Extrapyramidal Symptoms: 10 - 50 mg IV or deep IM

Question 7

Diphenhydramine HCl (Benadryl)

Pediatric Dose?

Answer 7

Diphenhydramine HCl (Benadryl)

Pediatric Dose:

• 1 - 1.25 mg/kg slow IV push or deep IM

Question 8

Diphenhydramine HCl (Benadryl)

Onset of Action?

Answer 8

Diphenhydramine HCl (Benadryl)

Onset of Action:

• IV: 5 - 10 minutes

Question 9

Diphenhydramine HCl (Benadryl)

Peak Effects?

Answer 9

Diphenhydramine HCl (Benadryl)

Peak Effects:

• 1 hour

Question 10

Diphenhydramine HCl (Benadryl)

Duration of Action?

Answer 10

Diphenhydramine HCl (Benadryl)

Duration of Action:

• 3 - 6 hours

Question 11

Diphenhydramine HCl (Benadryl)

AZ Drug Box Minimum Supply?

Answer 11

Diphenhydramine HCl (Benadryl)

AZ Drug Box Minimum Supply:

• 50 mg