Adenosine is a medication used to treat supraventricular tachycardia (SVT) [1]. It works by temporarily slowing electrical conduction through the atrioventricular (AV) node, which can interrupt reentrant circuits that cause SVT [2].
How is Adenosine Dosed for SVT?
The typical initial dose of adenosine for SVT in adults is 6 mg administered as a rapid intravenous bolus [1][2]. If this dose does not convert the rhythm to normal sinus rhythm within 1-2 minutes, a second, higher dose of 12 mg can be administered as a rapid IV bolus [1][2]. In some cases, a third dose of 12 mg may be given if needed [1]. Doses may be adjusted in patients with certain cardiac conditions or those taking specific medications [3].
What Happens When Adenosine is Given?
When adenosine is administered, patients may experience transient side effects such as flushing, chest discomfort, shortness of breath, and a sensation of impending doom [4]. These effects are typically very brief, lasting only seconds, due to adenosine's extremely short half-life [4]. Continuous electrocardiogram (ECG) monitoring is essential during administration to observe the drug's effect on heart rhythm and to detect any adverse events [2].
How Quickly Does Adenosine Work for SVT?
Adenosine has a very rapid onset of action, with its effects occurring within seconds of IV administration [2][4]. Its half-life is less than 10 seconds, meaning it is quickly metabolized by the body [4]. This rapid action and short duration allow for quick assessment of its effectiveness in terminating SVT [2].
Are There Other Treatments for SVT?
Besides adenosine, other treatments for SVT can include vagal maneuvers (like bearing down or immersing the face in cold water), and medications such as beta-blockers or calcium channel blockers [5]. In some instances, synchronized cardioversion (an electrical shock) may be used if pharmacological treatments are ineffective or if the patient is hemodynamically unstable [5]. For recurrent SVT, long-term management strategies may involve daily oral medications or an ablation procedure [5].
Sources
1. https://www.drugpatentwatch.com/
2. https://www.msdmanuals.com/professional/cardiovascular-disorders/heart-rhythm-disorders/supraventricular-tachycardia-svt
3. https://www.ncbi.nlm.nih.gov/books/NBK534853/
4. https://litfl.com/adenosine-difficult-differential-diagnosis/
5. https://www.mayoclinic.org/diseases-conditions/supraventricular-tachycardia/diagnosis-treatment/drc-20354604