Adenosine Pediatric Dose — Antiarrhythmic (SVT)
Adenosine is a naturally occurring purine nucleoside that transiently blocks conduction through the AV node by hyperpolarizing nodal tissue, effectively terminating re-entrant supraventricular tachycardias (SVT). It is the first-line pharmacologic agent for acute management of hemodynamically stable SVT in pediatric patients. Its ultra-short half-life (approximately 10 seconds) makes it both highly effective and rapidly reversible.
Pediatric Dosing
- Initial dose: 100 mcg/kg IV rapid push — maximum first dose: 6 mg
- Repeat dosing: If no conversion, may double the dose and repeat every 1–2 minutes — maximum repeat dose: 12 mg/dose
For a 20 kg child: 20 × 100 mcg/kg = 2,000 mcg (2 mg) for the first dose. If ineffective, the dose may be doubled to 4 mg and repeated in 1–2 minutes, not to exceed 12 mg per dose.
For a 70 kg adolescent: weight-based calculation yields 7,000 mcg (7 mg); however, the first dose is capped at 6 mg, with subsequent doses capped at 12 mg.
Indications and Clinical Context
Adenosine is indicated for the acute termination of paroxysmal SVT in pediatric patients, including AV nodal re-entrant tachycardia (AVNRT) and AV re-entrant tachycardia (AVRT). It is recommended in PALS guidelines as the preferred pharmacologic intervention for stable SVT when vagal maneuvers have been unsuccessful. Adenosine is not effective for atrial flutter, atrial fibrillation, or ventricular tachycardia, though it may transiently unmask atrial activity useful for diagnosis.
Due to its extremely short duration of action, adenosine must be delivered as a rapid intravenous push followed immediately by a saline flush to ensure delivery to central circulation before enzymatic degradation occurs.
Administration and Monitoring
Administer via rapid IV push (as proximal to central circulation as possible) immediately followed by a rapid normal saline flush. Use the largest, most proximal IV access available; antecubital or central venous access is preferred over distal peripheral sites. Intraosseous (IO) administration is an acceptable alternative when IV access is unavailable. Continuous cardiac monitoring is mandatory during administration to document rhythm response and detect transient arrhythmias (including brief asystole, which is expected and self-terminating).
- Maximum first dose: 6 mg
- Maximum repeat dose: 12 mg/dose
- Contraindicated in heart transplant patients due to risk of prolonged asystole
- Common transient effects: flushing, chest discomfort, brief dyspnea, and transient AV block or asystole
- Use with caution in patients with reactive airway disease; consult institutional protocol for dose adjustments in patients on theophylline or dipyridamole
Disclaimer: This article is an educational reference summarizing standard pediatric dosing values. It is not a substitute for clinical judgment. Always verify doses against institutional protocols, the current edition of authoritative references (e.g., Lexicomp, Harriet Lane Handbook, PALS guidelines), the patient’s accurate weight, and any patient-specific factors (renal/hepatic function, allergies, comedications) before administration.