Adenosine

U.S. BRAND NAMES — Adenocard®; Adenoscan®
PHARMACOLOGIC CATEGORY Antiarrhythmic Agent, Class IVDiagnostic Agent
DOSING: ADULTS Paroxysmal supraventricular tachycardia (Adenocard®): I.V. (rapid - over 1-2 seconds, via peripheral line): 6 mg; if not effective within 1-2 minutes, 12 mg may be given; may repeat 12 mg bolus if needed; maximum single dose: 12 mg. Follow each I.V. bolus of adenosine with normal saline flush. Note: Preliminary results in adults suggest adenosine may be administered via a central line at lower doses (ie, initial adult dose: 3 mg).
Pharmacologic stress agent (Adenoscan®): I.V.: Continuous I.V. infusion via peripheral line: 140 mcg/kg/minute for 6 minutes using syringe or columetric infusion pump; total dose: 0.84 mg/kg. Thallium-201 is injected at midpoint (3 minutes) of infusion.
Acute vasodilator testing (unlabeled use) (Adenoscan®): I.V.: Initial: 50 mcg/kg/minute increased by 50 mcg/kg/minute every 2 minutes to a maximum dose of 500 mcg/kg/minute; acutely assess vasodilator response
DOSING: PEDIATRIC
(For additional information see "Adenosine: Pediatric drug information")Paroxysmal supraventricular tachycardia (Adenocard®): Rapid I.V. push (over 1-2 seconds) via peripheral line: Infants and Children (manufacturer's recommendation): Children <50 kg: 0.05-0.1 mg/kg. If conversion of PSVT does not occur within 1-2 minutes, may increase dose by 0.05-0.1 mg/kg. May repeat until sinus rhythm is established or to a maximum single dose of 0.3 mg/kg or 12 mg. Follow each dose with normal saline flush. Children 50 kg: Refer to adult dosing.
Pediatric advanced life support (PALS): Treatment of SVT: I.V., I.O.: 0.1 mg/kg; if not effective, administer 0.2 mg/kg; maximum single dose: 12 mg. Follow each dose with normal saline flush.
DOSING: ELDERLY — Refer to adult dosing. Elderly may be more sensitive to effects of adenosine.
DOSING: RENAL IMPAIRMENT Hemodialysis: Significant drug removal is unlikely based on physiochemical characteristics.
Peritoneal dialysis: Significant drug removal is unlikely based on physiochemical characteristics.
Note: Higher doses may be needed for administration via peripheral versus central vein.
DOSAGE FORMS — Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Injection, solution [preservative free]: 3 mg/mL (2 mL, 4 mL) Adenocard®: 3 mg/mL (2 mL, 4 mL) Adenoscan®: 3 mg/mL (20 mL, 30 mL)
DOSAGE FORMS: CONCISE Injection, solution [preservative free]: 3 mg/mL (2 mL, 4 mL) Adenocard®: 3 mg/mL (2 mL, 4 mL) Adenoscan®: 3 mg/mL (20 mL, 30 mL)
GENERIC EQUIVALENT AVAILABLE — Yes
ADMINISTRATION — For rapid bolus I.V. use only; administer I.V. push over 1-2 seconds at a peripheral I.V. site as proximal as possible to trunk (not in lower arm, hand, lower leg, or foot); follow each bolus with normal saline flush. Note: Preliminary results in adults suggest adenosine may be administered via central line at lower doses (eg, adults initial dose: 3 mg)
COMPATIBILITY — Stable in D5LR, D5W, LR, NS.
USE Adenocard®: Treatment of paroxysmal supraventricular tachycardia (PSVT) including that associated with accessory bypass tracts (Wolff-Parkinson-White syndrome); when clinically advisable, appropriate vagal maneuvers should be attempted prior to adenosine administration; not effective in atrial flutter, atrial fibrillation, or ventricular tachycardia
Adenoscan®: Pharmacologic stress agent used in myocardial perfusion thallium-201 scintigraphy
USE - UNLABELED / INVESTIGATIONAL — Adenoscan®: Acute vasodilator testing in pulmonary artery hypertension
ADVERSE REACTIONS SIGNIFICANT — Note: Frequency varies based on use; higher frequency of infusion-related effects, such as flushing and lightheadedness, were reported with continuous infusion (Adenoscan®).
>10%: Cardiovascular: Facial flushing (18% to 44%) Central nervous system: Headache (2% to 18%), lightheadedness (2% to 12%) Neuromuscular & skeletal: Discomfort of neck, throat, jaw (<1% to 15%) Respiratory: Dyspnea (12% to 28%), chest pressure/discomfort (7% to 40%)
1% to 10%: Cardiovascular: Hypotension (<1% to 2%), AV block (infusion 6%; third degree <1%), ST segment depression (3%), palpitation, chest pain Central nervous system: Dizziness, nervousness (2%), apprehension Gastrointestinal: Nausea (3%) Neuromuscular & skeletal: Upper extremity discomfort (up to 4%), numbness (up to 2%), paresthesia (up to 2%) Respiratory: Hyperventilation Miscellaneous: Diaphoresis
<1% (Limited to important or life-threatening): Asystole (prolonged), atrial fibrillation, back discomfort, bradycardia, bronchospasm, blurred vision, burning sensation, hypertension (transient), injection site reaction, intracranial pressure increased, metallic taste, pressure in groin, respiratory arrest, seizure, torsade de pointes, ventricular fibrillation, ventricular tachycardia
CONTRAINDICATIONS — Hypersensitivity to adenosine or any component of the formulation; second- or third-degree AV block or sick sinus syndrome (except in patients with a functioning artificial pacemaker), atrial flutter, atrial fibrillation, and ventricular tachycardia (this drug is not effective in converting these arrhythmias to sinus rhythm). The manufacturer states that Adenoscan® should be avoided in patients with known or suspected bronchoconstrictive or bronchospastic lung disease.
WARNINGS / PRECAUTIONS Concerns related to adverse effects: Atrial fibrillation/flutter: There have been reports of atrial fibrillation/flutter in patients with paroxysmal supraventricular tachycardia (PSVT) associated with accessory conduction pathways after adenosine. Does not convert afib/flutter to normal sinus rhythm; risk of serious arrhythmias/hypotension. Not for use in patients with afib/flutter associated with Wolff-Parkinson-White Syndrome. Conduction disturbances: Adenosine decreases conduction through the AV node and may produce first-, second-, or third-degree heart block. Patients with pre-existing S-A nodal dysfunction may experience prolonged sinus pauses after adenosine; use caution in patients with first-degree AV block or bundle branch block; avoid use of adenosine for pharmacologic stress testing in patients with high-grade AV block or sinus node dysfunction (unless a functional pacemaker is in place). Rare, prolonged episodes of asystole have been reported, with fatal outcomes in some cases. Hypotension: May produce profound vasodilation with subsequent hypotension. When used as a bolus dose (PSVT), effects are generally self-limiting (due to the short half-life of adenosine). However, when used as a continuous infusion (pharmacologic stress testing), effects may be more pronounced and persistent, corresponding to continued exposure. Use infusions with caution in patients with autonomic dysfunction, carotid stenosis (with cerebrovascular insufficiency), uncorrected hypovolemia, pericarditis, pleural effusion and/or stenotic valvular heart disease. Proarrhythmic effects: Watch for proarrhythmic effects; monitor and adjust dose to prevent QTc prolongation.
Disease-related concerns: Asthma: A limited number of patients with asthma have received adenosine and have not experienced exacerbation of their asthma. Adenosine may cause bronchoconstriction in patients with asthma; should be used cautiously in patients with obstructive lung disease not associated with bronchoconstriction (eg, emphysema, bronchitis). Electrolyte imbalance: Correct electrolyte disturbances, especially hypokalemia or hypomagnesemia, prior to use and throughout therapy.
Concurrent drug therapy issues: Caffeine: Pharmacologic stress testing: Withhold for five half-lives prior to adenosine use; avoid dietary caffeine for 12-24 hours prior to pharmacologic stress testing. Drugs which slow AV conduction: Use with caution in patients receiving other drugs which slow AV conduction (eg, digoxin, verapamil). Theophylline: Withhold for five half-lives prior to adenosine use whenever possible (eg, pharmacological stress testing).
Special populations: Elderly: Use with caution in the elderly; may be at increased risk of hemodynamic effects, bradycardia, and/or AV block.
Dosage form specific issues: Adenocard®: Transient AV block is expected. When used in PSVT, at the time of conversion to normal sinus rhythm, a variety of new rhythms may appear on the ECG. Administer as a rapid bolus, either directly into a vein or (if administered into an I.V. line), as close to the patient as possible (followed by saline flush).
Other warnings/precautions: CAST trial: In the Cardiac Arrhythmia Suppression Trial (CAST), recent (>6 days but <2 years ago) myocardial infarction patients with asymptomatic, nonlife-threatening ventricular arrhythmias did not benefit and may have been harmed by attempts to suppress the arrhythmia with flecainide or encainide. An increased mortality or nonfatal cardiac arrest rate (7.7%) was seen in the active treatment group compared with patients in the placebo group (3%). The applicability of the CAST results to other populations is unknown. Antiarrhythmic agents should be reserved for patients with life-threatening ventricular arrhythmias.
DRUG INTERACTIONS Carbamazepine may increase heart block.
Dipyridamole potentiates effects of adenosine; reduce dose of adenosine.
Theophylline and caffeine (methylxanthines) antagonize adenosine's effects; may require increased dose of adenosine.
ETHANOL / NUTRITION / HERB INTERACTIONS — Food: Avoid food or drugs with caffeine. Adenosine's therapeutic effect may be decreased if used concurrently with caffeine. Avoid dietary caffeine for 12-24 hours prior to pharmacologic stress testing.
PREGNANCY RISK FACTOR — C (show table)
PREGNANCY IMPLICATIONS — Reports of administration during pregnancy have indicated no adverse effects on fetus or newborn attributable to adenosine.
LACTATION — Excretion in breast milk unknown
DIETARY CONSIDERATIONS — Avoid dietary caffeine for 12-24 hours prior to pharmacologic stress testing.
MONITORING PARAMETERS — ECG monitoring, heart rate, blood pressure
TOXICOLOGY / OVERDOSE COMPREHENSIVE — Since the half-life of adenosine is <10 seconds, any adverse effects are rapidly self-limiting. Intoxication is usually short-lived since the half-life of the drug is very short. Treatment of prolonged effects requires individualization. Theophylline and other methylxanthines are competitive inhibitors of adenosine and may have a role in reversing its toxic effects. To reverse the effects of Adenoscan®, administer theophylline 50-125 mg slow I.V. push.
CANADIAN BRAND NAMES — Adenocard®; Adenoscan®; Adenosine Injection, USP
INTERNATIONAL BRAND NAMES — Adenocard (BR, CA); Adenocor (AU, BE, BG, CN, CZ, DK, EC, EE, EG, ES, FI, GB, HU, IE, IL, KR, MY, NO, NZ, PE, PL, TH, TW, UY, VE, ZA); Adenocur (NL); Adenoject (IN); Adenoscan (CA, HK); Adenosin Ebewe (PL); Adenosina Biol (AR, PY); Adenosine Injection, USP (CA); Adrekar (AT, DE); Cardiovert (PH); Fosfobion (PL); Krenosin (FR, IT, MX); Krenosine (CH); Soladen (PL)
MECHANISM OF ACTION — Slows conduction time through the AV node, interrupting the re-entry pathways through the AV node, restoring normal sinus rhythm
PHARMACODYNAMICS / KINETICS Onset of action: Rapid
Duration: Very brief
Metabolism: Blood and tissue to inosine then to adenosine monophosphate (AMP) and hypoxanthine
Half-life elimination: <10 seconds