Intelligent Beverages LLC launched Resqwater, which was designed to prevent a hangover after a night of drinking. The dietary supplement helps the body metabolize acetaldehyde, which is the enzyme responsible for a hangover, by using N-acetyl L-cysteine to convert acetaldehyde into acetic acid, the company says. It also contains water, sucrose, prickly pear cactus fruit extract, electrolytes, B vitamins and milk thistle to replenish the body and fight hangover symptoms, it adds. An 8-ounce bottle retails for approximately $4.49.