“Woe to you, my princess, when I come. I will kiss you quite red and feed you till you are plump. And if you are forward you shall see who is the stronger, a gentle little girl who doesn’t eat enough or a big wild man who has cocaine in his body,” wrote Sigmund Freud to his future wife, Martha Bernays, on June 2, 1884. On February 2, 1886, toward the end of another letter to Bernays, Freud wrote, “Here I am, making silly confessions to you, my sweet darling, and really without any reason whatever unless it is the cocaine that makes me talk so much.” The two married later that year.

The questions “Have you ever used Derbisol?” and “How often?” sometimes appear along with questions about alcohol, cocaine, and marijuana use on youth-risk surveys for students. Derbisol is a fictitious drug devised to test the reliability of the responder. In one survey, 163 of 894 students said that they had tried Derbisol—or 18.2 percent.