Atropine Dosing Chart Per Kilogram Weight
Pediatric Dosing by Clinical Indication
Symptomatic Bradycardia and AV Block
The standard dose for symptomatic bradycardia in children is 0.02 mg/kg IV/IO, with a minimum single dose of 0.1 mg and maximum single dose of 0.5 mg (1.0 mg for adolescents), repeatable every 5 minutes up to a total of 1 mg in children or 2 mg in adolescents 1.
- Initial dose: 0.02 mg/kg IV/IO 1
- Minimum single dose: 0.1 mg (to avoid paradoxical bradycardia) 1
- Maximum single dose:
- Repeat interval: Every 5 minutes as needed 1
- Maximum total dose:
Critical first step: Ensure adequate oxygenation and ventilation before administering atropine, as hypoxia-induced bradycardia typically responds to these interventions alone 2, 3. If oxygen and ventilation fail to correct bradycardia, epinephrine—not atropine—is the drug of choice 3.
Neonatal Dosing Exception
For neonates, the dose is 0.01–0.03 mg/kg IV/IO with NO minimum dose requirement 2, 3, 4.
- The 2015 American Heart Association guidelines eliminated the previous 0.1 mg minimum dose requirement for neonates after evidence demonstrated that 0.02 mg/kg without a minimum dose is both effective and safe 3.
- The outdated minimum dose recommendation was based on reports of paradoxical bradycardia with very low doses, but recent evidence refutes this concern in neonates 3, 5.
Organophosphate/Carbamate Poisoning
For anticholinesterase poisoning, administer 0.02–0.05 mg/kg IV (maximum single dose 2–3 mg), repeated and doubled every 10–20 minutes until full atropinization is achieved 1, 2.
- Initial dose: 0.02–0.05 mg/kg IV 1, 2
- Maximum single dose: 2–3 mg 1
- Escalation strategy: Double the dose every 10–20 minutes if response is inadequate 1, 2
- Therapeutic endpoints indicating adequate atropinization:
- Maintenance infusion: After bolus dosing, use 10–20% of the total loading dose per hour (up to 2 mg/h in adults) 1
- Essential adjunctive therapy: Combine atropine with pralidoxime (oxime) to address nicotinic receptor dysfunction and benzodiazepines for seizure control 1, 2
Common pitfall: Do not withhold adequate atropine doses in organophosphate poisoning due to fear of overdose—inadequate dosing can be fatal 2. Adult patients may require 10–20 mg in the first 2–3 hours and up to 50 mg in 24 hours before full muscarinic antagonism appears 2.
Rapid Sequence Intubation (RSI) Premedication
For RSI premedication, administer 0.01–0.02 mg/kg IV/IO (minimum 0.1 mg, maximum 1 mg) before sedative/anesthetic and paralytic agents 2, 3.
- This dose mitigates bradycardia during intubation 2.
- Important caveat: Do not routinely use atropine for RSI premedication in all pediatric patients, as it may be unnecessary for many 2.
Alternative Routes When IV/IO Access Is Unavailable
Endotracheal Administration
When IV/IO access is unavailable, administer atropine via endotracheal tube at 0.04–0.06 mg/kg for children and adolescents, followed by 5 mL saline flush and 5 ventilations 1.
| Population | ET Dose (mg/kg) | Additional Notes |
|---|---|---|
| Neonates | 0.01–0.03 | Follow with 1–5 mL saline flush based on size [2] |
| Children & Adolescents | 0.04–0.06 | Follow with 5 mL saline flush and 5 ventilations [1] |
- The endotracheal dose is 2–3 times the IV/IO dose to compensate for lower absorption 1.
- Stop chest compressions briefly during CPR, administer the medication, flush, and provide 5 positive-pressure ventilations 1.
Adult Dosing
For adults, the usual initial dose is 0.01–0.03 mg/kg IV 4.
- Patients with coronary artery disease: Limit the total dose to 0.03–0.04 mg/kg (maximum 2–3 mg total) to avoid detrimental tachycardia and increased myocardial oxygen demand 4.
- Titrate based on heart rate, PR interval, blood pressure, and symptoms 4.
Weight-Based Transition to Adult Dosing
Children weighing more than 40 kg should receive adult atropine dosing regimens (maximum single dose 1 mg, maximum total dose 2 mg) rather than pediatric dosing 2.
- The 40 kg threshold corresponds to the point where pharmacokinetic parameters approximate adult values 2.
- Age-based transition typically occurs at 12–15 years 2.
Critical Safety Considerations
Concentration Errors
Atropine sulfate is available in 0.1 mg/mL and 0.4 mg/mL concentrations—calculate doses carefully to avoid 10-fold errors, which are common in pediatric dosing 2, 3.
Administration Technique
- For cardiac arrest: Administer by slow IV push to avoid paradoxical bradycardia 3.
- Monitoring: Continuously monitor heart rate, blood pressure, and ECG during and after administration 2, 3.
- Peak action time: Observe for reversal of bradycardia within 3 minutes 2.
Contraindications and Cautions
- Do not use atropine for type II second-degree AV block or third-degree AV block with wide-complex escape rhythm—it is ineffective and potentially harmful 2.
- Tachycardia risk: Atropine-induced tachycardia can worsen ischemia in patients with acute coronary syndrome 3, 4.
- Other warnings: May precipitate acute glaucoma, complete urinary retention in prostatic hypertrophy, or viscid bronchial plugs in chronic lung disease 4.
Summary Dosing Table
| Indication | Pediatric Dose | Minimum Dose | Maximum Single Dose | Maximum Total Dose | Route |
|---|---|---|---|---|---|
| Symptomatic bradycardia | 0.02 mg/kg | 0.1 mg | 0.5 mg (child), 1.0 mg (adolescent) | 1 mg (child), 2 mg (adolescent) | IV/IO [1] |
| Neonatal bradycardia | 0.01–0.03 mg/kg | None | — | — | IV/IO [2,3,4] |
| Organophosphate poisoning | 0.02–0.05 mg/kg | — | 2–3 mg | No fixed limit (titrate to effect) | IV [1,2] |
| RSI premedication | 0.01–0.02 mg/kg | 0.1 mg | 1 mg | — | IV/IO [2,3] |
| Endotracheal (children) | 0.04–0.06 mg/kg | — | — | — | ET [1] |
| Adult | 0.01–0.03 mg/kg | — | — | 0.03–0.04 mg/kg (CAD) | IV [4] |