ATROPINE SULFATE

Question 1

Drug Classification

Answer 1

Anticholinergic / Parasympatholytic

Question 2

Mechanism of Action

Answer 2

Muscarinic ACh-R antagonist → inhibits parasympathetic stimulation in SA and AV nodal cells →prevents potassium efflux and hyperpolarization →positive chronotropy, no inotropic effect

Question 3

Pharmacokinetics

Answer 3

Onset of Action = Immediate
Peak Effects = 2-4 minutes
Duration of Effect = 4 hours
Half-Life = 2-3 hours

Question 4

Indications

Answer 4

Symptomatic Bradycardia
Premedication for RSI with Bradycardia <50bpm
Organophosphate poisioning

Question 5

Contraindications

Answer 5

None

Question 6

Side Effects

Answer 6

Tachycardia, dilated pupils, blurred vision, drowsiness, confusion, dry mouth

Question 7

Dose

Answer 7

Bradycardia (ADULT): 0.5mg IV, IO q 3-5 min up to 3mg
RSI (ADULT): 0.5 IV, IO
Organophosphate (ADULT): 2mg IV, IO, IM, q 5 min until S/S resolve
Bradycardia (PEDI): 0.02mg/kg IV, IO; minimum single dose 0.1mg; max single dose 0.5mg
RSI (PEDI): 0.02mg/kg IV, IO
Organophosphate (PEDI): 0.05mg/kg IV, IO, IM q 5 min until S/S resolve

Question 8

Precautions

Answer 8

Do not give less than 0.5mg (ADULT) or 0.1mg (PEDI) – causes paradoxical effect.
May cause paradoxical slowing or may be ineffective if used for 2°Type II / 3°heart block
Caution with acute MI – increases myocardial oxygen demand

Question 9

Drug Interactions

Answer 9

None