What is the second-dose adenosine amount after the first dose in pediatric dosing?

• A. 0.1 mg/kg (max 6 mg)
• B. 0.5 mg/kg
• C. 0.2 mg/kg (max 12 mg)
• D. 1 mg/kg

Answer: (C)

Adenosine dosing in pediatric SVT uses a small first dose followed by a higher second dose if the first one doesn’t terminate the tachycardia. The initial bolus is 0.1 mg/kg (max 6 mg). If the rhythm persists, the second dose is given at 0.2 mg/kg (max 12 mg). This doubling increases the chance of transient AV nodal block to interrupt the reentrant circuit, while still staying within safety limits. Administer as a rapid IV push with a saline flush and monitor closely for adverse effects.