Indication
Anesthesia Premedication
0.4-0.6 mg IV/IM/SC 30-60 minutes before anesthesia; repeat q4-6hr PRN
Sinus Bradycardia (ACLS)
0.5-1 mg or 0.04 mg/kg IV q5min, no more than 3 mg
Organophosphorus poisoning
Adult: 2 mg IV/IM, every 10-30 minutes until muscarinic effects disappear or atropine toxicity appears. In severe cases, dose can be given as often as every 5 minutes. In moderate to severe poisoning, a state of atropinisation is maintained for at least 2 days and continued for as long as symptoms are present.
Bronchospasm
0.025 mg/kg in 2.5 mL NS q6-8hr via nebulizer; no more than 2.5 mg/dose
Asystole/Pulseless Electrical Activity (ACLS)
1 mg IV q3-5min PRN if asystole persist up to 0.04 mg/kg
Administration
Additive anticholinergic effects with quinidine, antidepressants and some antihistamines.
Adult Dose
Reflux oesophagitis, elderly, infants and children. Pregnancy.
Lactation: Trace amounts enter breast milk; use with caution (AAP Committee states "compatible with nursing")
Renal Dose
Atropine is an anticholinergic agent which competitively blocks the muscarinic receptors in peripheral tissues such as the heart, intestines, bronchial muscles, iris and secretory glands. Some central stimulation may occur. Atropine abolishes bradycardia and reduces heart block due to vagal activity. Smooth muscles in the bronchi and gut are relaxed while glandular secretions are reduced. It also has mydriatic and cycloplegic effect.
Contraindication
Anesthesia Premedication
<5 kg: 0.02 mg/kg/dose 30-60 minutes preop; then q4-6hr PRN
>5 kg: 0.01-0.02 mg/kg IV/IM/SC; no more than 0.4 mg
Sinus Bradycardia
0.02 mg/kg IV/IO q5min for 2-3 doses PRN; single dose no less than: 0.1 no more than 0.5 mg (children), 1 mg (adolescents)
Total: No more than: 1 mg (children)
Bronchospasm
0.025-0.05 mg/kg in 2.5 mL NS q6-8hr via nebulizer; no more than 2.5 mg/dose
Organophosphate or Carbamate Poisoning
IV: 0.03-0.05 mg/kg IV/IM/IO/ET q10-20min PRN to effect; then q1-4hr for at least 24 hours
Precaution
Bradycardia, Organophosphorus poisoning, Anesthesia adjunct
Pregnancy Category Note
Dry mouth, dysphagia, constipation, flushing and dryness of skin, tachycardia, palpitations, arrhythmias, mydriasis, photophobia, cycloplegia, raised intraocular pressure. Toxic doses cause tachycardia, hyperpyrexia, restlessness, confusion, excitement, hallucinations, delirium and may progress to circulatory failure and resp depression.
Inhalation: Dryness of mouth, throat.
Potentially Fatal: Atrial arrhythmias, AV dissociation, multiple ventricular ectopics.
Interaction
Glaucoma, chronic respiratory disease, sick sinus syndrome, thyrotoxicosis, cardiac failure, pyloric stenosis, prostatic hypertrophy.