Atropine

Question 1

Classification

Answer 1

Parasympathetic (anticholinergic, antimuscarinic)

Question 2

Mechanism of Action

Answer 2

• Competes reversibly with acetylcholine at the site of the muscarinic receptor.
• Receptors affected in order from most to least sensitive, salivary, bronchia, sweat glands, eye, heart, and GI tract
• Increases heart rate

Question 3

Indications

Answer 3

• Symptomatic bradycardia, asystole or PEA
• Nerve agent exposure
• Organophosphate poisoning

Question 4

Contraindications

Answer 4

• Known sensitivity to atropine, belladonna alkaloids, or sulfites

Question 5

Adverse Effects

Answer 5

• Decreases secretions result in dry mouth and hot skin temperature, intense facial flushing, blurred vision, or dilation of pupils with subsequent photophobia.
• May cause paradoxical bradycardia if dose is too low or pushed too slowly.

Question 6

Administration

Answer 6

• Symptomatic Bradycardia
  
  • Adult: 0.5 mg IV/IO every 3-5 minutes to a max of 3 mg.
  • Pediatrics: .02 mg/kg (min .1 mg/dose, max .5 mg/dose) IV/IO total dose of 1 mg.
• Asystole/PEA
  
  • ​1 mg IV/IO every 3-5 minutes, max dose 3 mg. May be administered ETT at 2-2.5 mg diluted in 5-10 ml of water or NS.
• Nerve Agent or Organophosphate Poisoning
  
  • ​​​2-4 mg IV/IO/IM, repeat if needed eery 20-30 minutes until symptoms resolve. In severe cases doses may be as large as 2-6 mg IV.

Question 7

Special Considerations

Answer 7

• Half Life 2.5 hours
• Closed angle glaucoma
• May not be effective for high-degree AV blocks.