who took digoxin died "more frequently" (33%) than women who took placebo (29%). Digoxin increased the risk of death in women by 23%. There was no difference in the death rate for men in the study. Digoxin is also used as a standard control substance to test for P-glycoprotein inhibition. Digoxin appears to be a peripherally selective drug due to limited brain uptake caused by binding to P-glycoprotein. Pharmacomicrobiomics The bacteria Eggerthella lenta has been linked to a decrease in the toxicity of Digoxin. These effects have been studied through comparisons of North Americans and Southern Indians, in which a reduced digoxin metabolite profile correlates with E. lenta abundance. Further studies have also revealed an increase in digoxin toxicity when used alongside erythromycin or tetracycline, the researches attributed this to the decrease in the E. lenta population. Overall, bacterial inactivation of Digoxin occurs often. This is why Digoxin is given as a capsule or as a solution in capsule. History Derivatives of plants of the genus Digitalis have a long history of medical use. Nicholas Culpeper referred to various medical uses for Foxglove in his 1652 publication The English physician. William Withering is credited with the first published description of the systematic use of Digitalis derivatives in his 1785 book An Account of the Foxglove and some of its Medical Uses With Practical Remarks on Dropsy and Other Diseases. Its use was somewhat sporadic until Sir James Mackenzie identified the phenomenon of atrial fibrillation, and the actions of digitalis on this. Its effects were first explained by Arthur Robertson Cushny. The name is a portmanteau, derived from Digitalis lanata and toxin. In 1930, Digoxin was first isolated by Dr. Sydney Smith from the foxglove plant, Digitalis lanata. Initially, the digoxin was purified by dissolving the dried plant material in acetone and boiling the solution in chloroform. The solution was then reacted with acetic acid and small amount of ferric chloride and sulfuric acid (Keller reaction). Digoxin was distinguishable from other glucosides by the olive-green colored solution produced from this reaction, completely free of red. Society and culture Charles Cullen admitted in 2003 to killing as many as 40 hospital patients with overdoses of heart medication—usually digoxin—at hospitals in New Jersey and Pennsylvania over his 19-year career as a nurse. On March 10, 2006, he was sentenced to 18 consecutive life sentences and is not eligible for parole. On April 25,