Adenosine

What it is used for

Conversion to sinus rhythm of paroxysmal supraventricular tachycardia (PSVT), including that associated with accessory bypass tracts (Wolff-Parkinson-White Syndrome). When clinically advisable, appropriate vagal maneuvers (e.g., Valsalva maneuver), should be attempted prior to adenosine injection administration.

It is important to be sure the adenosine injection solution actually reaches the systemic circulation (see DOSAGE AND ADMINISTRATION ).

Adenosine Injection does not convert atrial flutter, atrial fibrillation, or ventricular tachycardia to normal sinus rhythm. In the presence of atrial flutter or atrial fibrillation, a transient modest slowing of ventricular response may occur immediately following adenosine injection administration.

How to take it

For rapid bolus intravenous use only.

Adenosine Injection, USP should be given as a rapid bolus by the peripheral intravenous route. To be certain the solution reaches the systemic circulation, it should be administered either directly into a vein or, if given into an IV line, it should be given as close to the patient as possible and followed by a rapid saline flush.

Side effects, and when to stop

The following reactions were reported with intravenous adenosine injection used in controlled U.S. clinical trials. The placebo group had a less than 1% rate of all of these reactions.

Cardiovascular

Facial flushing (18%), headache (2%), sweating, palpitations, chest pain, hypotension (less than 1%).

Respiratory

Shortness of breath/dyspnea (12%), chest pressure (7%), hyperventilation, head pressure (less than 1%).

Central Nervous System

Lightheadedness (2%), dizziness, tingling in arms, numbness (1%), apprehension, blurred vision, burning sensation, heaviness in arms, neck and back pain (less than 1%).

Gastrointestinal

Nausea (3%), metallic taste, tightness in throat, pressure in groin (less than 1%).

Who should not take it

Intravenous adenosine injection is contraindicated in:

• Second- or third-degree A-V block (except in patients with a functioning artificial pacemaker).
• Sinus node disease, such as sick sinus syndrome or symptomatic bradycardia (except in patients with a functioning artificial pacemaker).
• Known hypersensitivity to adenosine.

Other medicines and interactions

Intravenous adenosine injection has been effectively administered in the presence of other cardioactive drugs, such as quinidine, beta-adrenergic blocking agents, calcium channel blocking agents, and angiotensin converting enzyme inhibitors, without any change in the adverse reaction profile. Digoxin and verapamil use may be rarely associated with ventricular fibrillation when combined with adenosine injection (see WARNINGS ). Because of the potential for additive or synergistic depressant effects on the SA and AV nodes, however, adenosine injection should be used with caution in the presence of these agents. The use of adenosine injection in patients receiving digitalis may be rarely associated with ventricular fibrillation (see WARNINGS ).

The effects of adenosine are antagonized by methylxanthines such as caffeine and theophylline. In the presence of these methylxanthines, larger doses of adenosine may be required or adenosine may not be effective. Adenosine effects are potentiated by dipyridamole. Thus, smaller doses of adenosine may be effective in the presence of dipyridamole. Carbamazepine has been reported to increase the degree of heart block produced by other agents. As the primary effect of adenosine is to decrease conduction through the A-V node, higher degrees of heart block may be produced in the presence of carbamazepine.

Storing it

Store at 20° to 25°C (68° to 77°F).

DO NOT REFRIGERATE as crystallization may occur. If crystallization has occurred, dissolve crystals by warming to room temperature. The solution must be clear at the time of use.

Discard unused portion.

Sterile, Nonpyrogenic, Preservative-free. The container closure is not made with natural rubber latex.