Adenosine

Name: Adenosine

Actions

  • Slows conduction time through the AV node; can interrupt reentrant pathways through the AV node and restore normal sinus rhythm in patients with PSVT, including that associated with Wolff-Parkinson-White syndrome.1 4

  • Increases blood flow in normal coronary arteries with little or no increase in stenotic arteries, resulting in a greater difference in thallous (thallium) chloride TI 201 uptake in myocardium supplied by normal versus stenotic coronary arteries.2 28

  • Potent vasodilator in most vascular beds; however, vasoconstriction is produced in renal afferent arterioles and hepatic veins.1 2 4

  • Produces a net mild to moderate reduction in systolic, diastolic, and mean arterial blood pressure and a reflex increase in heart rate.2 12

  • May exert pharmacologic effects by activation of purine (cell-surface A1 and A2 adenosine) receptors; relaxation of vascular smooth muscle may be mediated by reduction in calcium uptake through inhibition of slow inward calcium current and activation of adenylate cyclase in smooth muscle cells.2 4

  • May reduce vascular tone by modulation of sympathetic neurotransmission.2

  • Respiratory stimulant, probably because of activation of carotid body chemoreceptors; IV administration produces an increase in minute ventilation and a reduction in arterial PCO2 resulting in respiratory alkalosis.1 2 12

If OVERDOSE is suspected

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

How do I store and/or throw out Adenosine?

  • If you need to store this medicine at home, talk with your doctor, nurse, or pharmacist about how to store it.

Package/Label Display Panel

NDC 67457-856-20

Adenosine Injection, USP

60 mg per 20 mL

(3 mg per mL)

For Intravenous Infusion Only

Mylan

Rx only

Single-Dose Vial

Brand Names U.S.

  • Adenocard
  • Adenoscan

Onset of Action

Rapid

Duration of Action

Very brief

Half-Life Elimination

<10 seconds

Dosing Adult

Paroxysmal supraventricular tachycardia (Adenocard): IV (rapid, over 1 to 2 seconds, via peripheral line; see Note): Initial: 6 mg; if not effective within 1 to 2 minutes, 12 mg may be given; may repeat 12 mg bolus if needed (maximum single dose: 12 mg). Follow each dose with 20 mL normal saline flush. Note: Initial dose of adenosine should be reduced to 3 mg if patient is currently receiving carbamazepine or dipyridamole, has a transplanted heart or if adenosine is administered via central line (ACLS 2010; Chang 2002). A subsequent bolus dose of 18 mg (following an initial dose of 6 mg and a repeat bolus dose of 12 mg) has reportedly been used in patients with sustained SVTs (ACC/AHA/HRS [Page 2015]; Domanovits 1994).

Pharmacologic stress testing (Adenoscan): IV: Continuous IV infusion via peripheral line: 140 mcg/kg/minute for 6 minutes using syringe or volumetric infusion pump; total dose: 840 mcg/kg. Thallium-201 is injected at midpoint (3 minutes) of infusion.

Acute vasodilator testing in pulmonary artery hypertension (off-label use) (Adenoscan): IV: Initial: 50 mcg/kg/minute increased by 50 mcg/kg/minute every 2 minutes to a maximum dose of 500 mcg/kg/minute (Schrader, 1992) or to a maximum dose of 350 mcg/kg/minute (ACCF/AHA [McLaughlin, 2009]; ESC/ERS/ISHLT [Galie 2009]; Zuo 2012); acutely assess vasodilator response

Drug Interactions

Caffeine and Caffeine Containing Products: May diminish the therapeutic effect of Adenosine. Management: Monitor for decreased effect of adenosine if patient is receiving caffeine. Discontinue caffeine in advance of scheduled diagnostic use of adenosine whenever possible. Consider therapy modification

CarBAMazepine: May enhance the adverse/toxic effect of Adenosine. Specifically, the risk of higher degree heart block may be increased. Management: Consider using a lower initial dose of adenosine in patients who are receiving carbamazepine. Consider therapy modification

Digoxin: May enhance the adverse/toxic effect of Adenosine. Monitor therapy

Dipyridamole: May enhance the adverse/toxic effect of Adenosine. Specifically, cardiovascular effects of adenosine may be enhanced. Adenosine dose reduction may be needed. Management: Reduction of the initial dose of adenosine may be warranted. Consider therapy modification

Nicotine: May enhance the AV-blocking effect of Adenosine. Nicotine may enhance the tachycardic effect of Adenosine. Monitor therapy

Theophylline Derivatives: May diminish the therapeutic effect of Adenosine. Consider therapy modification

Warnings/Precautions

Concerns related to adverse effects:

• Atrial fibrillation/flutter: There have been reports of atrial fibrillation/flutter when administered to patients with paroxysmal supraventricular tachycardia (PSVT) and may be especially problematic in patients with PSVT and underlying Wolff-Parkinson-White syndrome; has also been reported in patients with or without a history of atrial fibrillation undergoing myocardial perfusion imaging with adenosine infusion.

• Cardiovascular events (Adenoscan): Cardiac arrest (fatal and nonfatal), myocardial infarction (MI), cerebrovascular accident (hemorrhagic and ischemic), and sustained ventricular tachycardia (requiring resuscitation) have occurred following Adenoscan use. Avoid use in patients with signs or symptoms of unstable angina, acute myocardial ischemia, or cardiovascular instability due to possible increased risk of significant cardiovascular consequences. Appropriate measures for resuscitation should be available during use.

• Conduction disturbances: Adenosine decreases conduction through the AV node and may produce first-, second-, or third-degree heart block. Patients with preexisting SA nodal dysfunction may experience prolonged sinus pauses after adenosine; use caution in patients with first-degree AV block or bundle branch block; use is contraindicated in patients with high-grade AV block, sinus node dysfunction, or symptomatic bradycardia (unless a functional artificial pacemaker is in place). Rare, prolonged episodes of asystole have been reported, with fatal outcomes in some cases. Discontinue adenosine in any patient who develops persistent or symptomatic high-grade AV block.

• Hypersensitivity: Hypersensitivity reactions (including dyspnea, pharyngeal edema, erythema, flushing, rash, or chest discomfort) have been reported following Adenoscan administration.

• Hypertension: Systolic and diastolic pressure increases have been observed with Adenoscan infusion. In most instances, blood pressure increases resolved spontaneously within several minutes; occasionally, hypertension lasted for several hours.

• 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), hypovolemia, pericarditis, pleural effusion and/or stenotic valvular heart disease; discontinue infusion in patients who develop persistent or symptomatic hypotension.

• Proarrhythmic effects: Monitor for proarrhythmic effects (eg, polymorphic ventricular tachycardia) during and shortly after administration/termination of arrhythmia. The benign transient occurrence of atrial and ventricular ectopy is common upon termination of arrhythmia.

• Seizures: Seizures (new-onset or recurrent) have been reported following Adenoscan administration; risk may be increased with concurrent use of aminophylline. Use of any methylxanthine (eg aminophylline, caffeine, theophylline) is not recommended in patients experiencing seizures associated with Adenoscan administration.

Disease-related concerns:

• Arrhythmia (wide-complex tachycardia): Avoid use in irregular or polymorphic wide-complex tachycardias; may cause degeneration to ventricular fibrillation (ACLS, 2010).

• Electrolyte imbalance: Correct electrolyte disturbances, especially hypokalemia or hypomagnesemia, prior to use and throughout therapy.

• Heart transplant recipients: Use with extreme caution in heart transplant recipients; adenosine may cause prolonged asystole; reduction of initial adenosine dose is recommended (ACLS, 2010); considered by some to be contraindicated in this setting (Delacrétaz, 2006).

• Pulmonary artery hypertension: Acute vasodilator testing (not an approved use): Use with extreme caution in patients with concomitant heart failure (LV systolic dysfunction with significantly elevated left heart filling pressures) or pulmonary veno-occlusive disease/pulmonary capillary hemangiomatosis; significant decompensation has occurred with other highly selective pulmonary vasodilators resulting in acute pulmonary edema.

• Respiratory disease: Avoid use in patients with bronchoconstriction or bronchospasm (eg, asthma); dyspnea, bronchoconstriction, and respiratory compromise have occurred during use. Per the ACLS guidelines and the manufacturer of Adenoscan, use considered contraindicated in patients with asthma. Use caution in patients with obstructive lung disease not associated with bronchoconstriction (eg, emphysema, bronchitis). Immediately discontinue therapy if severe respiratory difficulty is observed. Appropriate measures for resuscitation should be available during use.

• Wolff-Parkinson-White (WPW) syndrome: Adenosine should not be used in patients with WPW syndrome and preexcited atrial fibrillation/flutter since ventricular fibrillation may result (AHA/ACC/HRS [January, 2014]).

Concurrent drug therapy issues:

• Drug-drug interactions: Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information.

• Caffeine: Pharmacologic stress testing: Since caffeine antagonizes the activity of adenosine, withhold for 5 half-lives prior to adenosine use; avoid dietary caffeine for at least 12 hours prior to pharmacologic stress testing (Henzlova, 2006).

• Carbamazepine: Concomitant use potentiates the effects of adenosine; reduction of initial adenosine dose is recommended when used for SVT (ACLS, 2010).

• Dipyridamole: Concomitant use potentiates the effects of adenosine; reduction of initial adenosine dose is recommended when used for SVT (ACLS, 2010); withhold dipyridamole-containing medications for at least 24 hours prior to pharmacologic stress testing (Henzlova, 2006)

• Drugs which slow AV node conduction: Use with caution in patients receiving other drugs which slow AV node conduction (eg, digoxin, verapamil).

• Theophylline (includes aminophylline): Pharmacologic stress testing: Since theophylline antagonizes the activity of adenosine, withhold for 5 half-lives prior to adenosine use whenever possible.

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 IV line), as close to the patient as possible (followed by saline flush). Dose reduction recommended when administered via central line (ACLS, 2010).

Other warnings/precautions:

• Appropriate use: ECG monitoring is required during use. Equipment for resuscitation and trained personnel experienced in handling medical emergencies should always be immediately available. Adenosine does not convert atrial fibrillation/flutter to normal sinus rhythm; however, may be used diagnostically in these settings if the underlying rhythm is not apparent.

Adenosine and Pregnancy

Tell your doctor if you are pregnant or plan to become pregnant.

The FDA categorizes medications based on safety for use during pregnancy. Five categories - A, B, C, D, and X, are used to classify the possible risks to an unborn baby when a medication is taken during pregnancy.

Adenosine falls into category C:

In animal studies, pregnant animals were given this medication and had some babies born with problems. No well-controlled studies have been done in humans, though. Therefore, this medication may be used if the potential benefits to the mother outweigh the potential risks to the unborn child.

OR

There are no well-controlled studies that have been done in pregnant women. Adenosine should be used during pregnancy only if the possible benefit outweighs the possible risk to the unborn baby.

OR

No studies have been done in animals, and no well-controlled studies have been done in pregnant women. Adenosine should be given to a pregnant woman only if clearly needed.

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