Adenosine

See critical care quick reference for drug doses by weight.

General

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

Indications

• Conversion of reentrant PSVT to NSR

Adult Dosing

Stable, narrow complex tachycardia

• 6mg rapid IV push over 1-2s
  • If ineffective can try 12mg 2min later
  • If still ineffective can try another 12mg
• Caveat
  • For patients taking methylxanthines (ie caffeine, theophylline):
    • Blocks adenosine binding at receptor sites (competitive antagonist) and can lead to bronchospasm
  • Consider using lower dose (1st 3mg, 2nd/3rd 6mg) in patient taking carbamazepine (Tegretol), diazepam (Valium) or dipyridamole (Persantine) OR with a heart transplant.
• Traditionally given via stopcock with immediate flush secondary to very short half life. Newer study showing that you may be able to mix with normal saline and give as single push, however further evidence is still needed.

Pediatric Dosing

PALS guidelines for infants, children, and adolescents See critical care quick reference for drug doses by weight.

• 0.1mg/kg rapid IV/IO push (max 6mg/dose)
  • If not effective, increase to 0.2 mg/kg (max 12mg/dose)

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
  • Not defined - not renally eliminated
• Pediatric
  • Not defined - not renally eliminated

Hepatic Dosing

• Adult
  • Not defined - not hepatically eliminated
• Pediatric
  • Not defined - not hepatically eliminated

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