It was part of the 7 Up family of soft drinks, and it was introduced in June 2nd, 2002. It was launched in the same year as other attempts to extend soft drink brand names with new iterations, including Pepsi Blue, Dr. Pepper Red Fusion and Vanilla Coke. While dnL remained listed as an official product of the company in late 2005, it was scheduled to be discontinued in December 31st, 2005 in favor of the 7 Up Plus brand.
The product's name came from the fact that the "dnL" logo is the "7 Up" logo rotated 180°. As such, the product itself was, in many ways, the polar opposite of 7 Up: while 7 Up is caffeine-free, colorless, and comes in a green bottle, dnL contained caffeine, was colored vaguely similar to the green of 7 Up's bottle, and came in a clear bottle. And while 7 Up has a fairly standard lemon-lime flavor, dnL was a stronger lime-lemon/citrus flavor.
It was featured in SSX 3 as it’s sponsored drink.
The limited amount of marketing created for dnL focused on its "upside-down" theme, including its slogan, "Turn your thirst upside-down." The color was also similar to Pepsi's Mountain Dew soft drink, and, like Mountain Dew, was developed primarily to compete with The Coca-Cola Company's Sprite, Fanta, and Mello Yello.