Adenosine

See critical care quick reference for drug doses by weight.

General

• Type: Antiarrhythmics
• Dosage Forms: IV
• Common Trade Names: Adenocard, Adenoscan

Adult Dosing

Stable, narrow complex tachycardia

• 6mg rapid IV bolus over 1-2s
  • If ineffective can try 12mg 2min later
    • If still ineffective can try another 12mg
• Caveat
  • Higher dose (1st 12mg, 2nd/3rd 18mg) in patient taking methylxanthines (ie caffeine, theophylline)
    • Blocks adenosine binding at receptor sites (competitive antagonist)
    • Beware of bronchospasm in patient taking theophylline for reactive airway disease
  • Lower dose (1st 3mg, 2nd/3rd 6mg) in patient taking carbamazepine (Tegretol), diazepam (Valium) or dipyridamole (Persantine) OR with a heart transplant.

Indications

• Conversion of reentrant PSVT to NSR

Pediatric Dosing

See critical care quick reference for drug doses by weight.

Special Populations

Pregnancy Rating

• May use during pregnancy; risk of fetal harm not expected based on limited human data

Lactation

• Cardiac Stress Testing: may use while breastfeeding; no human data available, though risk of infant harm and adverse effects on milk production not expected based on drug properties.
• All other uses: N/A; drug unlikely to be used during breastfeeding based on indication

Renal Dosing

• Adult
• Pediatric

Hepatic Dosing

• Adult
• Pediatric

Contraindications

• Allergy to class/drug
• 2nd, 3rd AV block
• Sick sinus syndrome
• Reentrant SVTs not involving AV node are not terminated
• No effect on anterograde WPW

Adverse Reactions

• Bronchoconstriction (responds to bronchodilators)
• Bradyarrhythmia
• Hypotension(if given too slowly)

Pharmacology

• Kinetics: Onset of action = 20-30s Duration of action = 60-90s
• Half-life: <10 seconds
• Metabolism: vascular endothelial cells
• Excretion:

Mechanism of Action

• Negative inotropic, dromotropic, chronotropic effects
• Transient AV nodal block