<p>The structure of adenosine was first described in 1931,<sup class="text-reference-group"><a class="reference-popover-link" data-content="Levene PA, Tipson RS: THE RING STRUCTURE OF ADENOSINE. Science. 1931 Nov 20;74(1925):521. doi: 10.1126/science.74.1925.521. (PubMed ID 17798867)" href="#reference-A229823">7</a></sup> though the vasodilating effects were not described in literature until the 1940s.<sup class="text-reference-group"><a class="reference-popover-link" data-content="SINGHER HO, MILLMAN N: The adenosine-triphosphatase activity of smooth muscle. Fed Proc. 1946;5(1 Pt 2):202. (PubMed ID 21064444)" href="#reference-A229828">8</a></sup> Adenosine is indicated as an adjunct to thallium-201 in myocardial perfusion scintigraphy,<sup class="text-reference-group"><a class="reference-popover-link" data-content="FDA Approved Drug Products: Adenoscan (Adenosine) Intravenous Injection (Discontinued)" href="#reference-L31983">12</a></sup> though it is rarely used in this indication, having largely been replaced by <a href="https://go.drugbank.com/drugs/DB00975">dipyridamole</a> and [regadenson].<sup class="text-reference-group"><a class="reference-popover-link" data-content="Notghi A, Low CS: Myocardial perfusion scintigraphy: past, present and future. Br J Radiol. 2011 Dec;84 Spec No 3:S229-36. doi: 10.1259/bjr/14625142. (PubMed ID 22723530)" href="#reference-A229833">9</a>,<a class="reference-popover-link" data-content="Palani G, Ananthasubramaniam K: Regadenoson: review of its established role in myocardial perfusion imaging and emerging applications. Cardiol Rev. 2013 Jan-Feb;21(1):42-8. doi: 10.1097/CRD.0b013e3182613db6. (PubMed ID 22643345)" href="#reference-A229838">10</a></sup> Adenosine is also indicated in the treatment of supraventricular tachycardia.<sup class="text-reference-group"><a class="reference-popover-link" data-content="Dailymed: Adenocard (Adenosine) Intravenous Injection" href="#reference-L31998">13</a></sup></p><p>Adenosine was granted FDA approval on 30 October 1989.<sup class="text-reference-group"><a class="reference-popover-link" data-content="FDA Approved Drug Products: Adenocard (Adenosine) Intravenous Injection (Discontinued)" href="#reference-L31978">11</a></sup></p>