Adenosine: a new drug for acute termination of supraventricular tachycardia.

Adenosine, recently released for the acute termination of supraventricular tachycardia, is potentially the drug of first choice for this indication. Its notable effects are transient slowing of the sinus rate and atrioventricular nodal block. Adverse effects are transient and clinically insignificant, primarily because of the ultra-short half-life of the drug. Preliminary investigations suggest that adenosine may also be useful in the differential diagnosis of wide QRS complex tachycardias.