Endogenous purine nucleoside, AV-nodal blocking agentREQUIRES MONITORING

Adenosine

Adenosin Life Medical · Adenocor

First-line treatment for regular narrow-complex tachycardia when vagal manoeuvres have failed. Acts by blocking the AV node for a few seconds, making it both therapeutic for reentry involving the node and diagnostic for arrhythmias that do not — atrial flutter and atrial tachycardia are unmasked when the ventricular response is slowed. The half-life of a few seconds means both the effect and side effects are over before one can regret it, but requires that the injection be given rapidly followed by a flush.

BOXED WARNING

Never give in pre-excited atrial fibrillation — AV-nodal blockade can accelerate conduction via the accessory pathway and precipitate ventricular fibrillation. Contraindicated in severe asthma due to the risk of bronchospasm. A defibrillator must be immediately available.

Dosing in adults

By indicationuppdaterad 2026-08-22

Indication	Regimen	Comment
Regular narrow-complex tachycardia (PSVT)	6 mg iv as a rapid bolus over 1–2 s, immediately followed by 10–20 ml NaCl flush and raised arm; if no effect, 12 mg after 1–2 min, may be repeated once	the summary of product characteristics states 5 mg followed by 10 mg — same principle
Wide-complex tachycardia of uncertain origin	same dosing under continuous ECG recording	only for regular rhythm; never for irregular rhythm
Heart transplant recipient, dipyridamole treatment, or central line	starting dose 3 mg, titrate upward	markedly enhanced and prolonged effect
Pharmacological stress for myocardial scintigraphy	140 μg/kg/min iv for 4–6 min, radioisotope after 3 min	caffeine-free for 12 hours before
Children	0,1 mg/kg iv (max 6 mg), then 0,2–0,3 mg/kg (max 12 mg)	same rapid bolus technique

Renal impairment

No dose adjustment. Not eliminated via the kidneys but by adenosine deaminase in blood and endothelium.

Hepatic impairment

No dose adjustment. Not metabolised in the liver.

Children

0,1 mg/kg iv as rapid bolus (max 6 mg), if needed 0,2–0,3 mg/kg (max 12 mg).

Pitfall

Avoid in irregular wide-complex tachycardia — that presentation is pre-excited atrial fibrillation until proven otherwise, and AV-nodal blockade can then drive the rhythm to ventricular fibrillation. Also avoid in severe asthma. The most common reason for treatment failure is not the wrong dose but an injection that is too slow, a too-peripheral line, or a missing flush.

Pharmacokinetics

t½: < 10 seconds
ONSET: 10–20 seconds
EFFECT DURATION: under 1 minute
METABOLISM: Adenosine deaminase in erythrocytes and vascular endothelium
EXCRETION: No renal or hepatic elimination
ADMINISTRATION: Rapid bolus into proximal vein, immediate flush
ANTAGONISTS: Theophylline, caffeine
POTENTIATED BY: Dipyridamole, carbamazepine, denervation

Adverse effects by frequency

≥ 10 %

Flushing, dyspnoea and chest discomfort, anxiety, headache

1–10 %

Transient asystole or sinus arrest, bradycardia, nausea, metallic taste

< 1 %

Bronchospasm, atrial fibrillation, ventricular fibrillation in pre-excitation, coronary spasm

Monitoring schedule

Continuous ECG recording: during and 1 min after each dose
Blood pressure: before and after injection
Defibrillator and atropine: available at every administration
Respiratory effects in obstructive airway disease: at each dose

Interaction burden

12clinically significant

2 contraindicated · 4 major · 6 moderate. Theophylline and caffeine antagonise the effect and may require higher doses. Dipyridamole inhibits uptake and markedly enhances the effect — infusion is then contraindicated. Heart transplant recipients and patients with a central line have denervation hypersensitivity; start with 3 mg.

Formulation & cost

Injection solution 5 mg/ml, 2 ml ampoule: 10 mg per ampoule
Injection vial 5 mg/ml, 10 ml: 50 mg, for infusion during scintigraphy
Restriction: only under continuous ECG monitoring with defibrillator available