Laudanum /ˈlɔːdᵊnəm/ is a tincture of opium containing approximately 10% powdered opium by weight (the equivalent of 1% morphine).Reddish-brown and extremely bitter, laudanum contains almost all of the opium alkaloids, including morphine and codeine, and its high morphine concentration makes it a potent narcotic. Laudanum was historically used to treat a variety of ailments, but its principal use was as an analgesic and cough suppressant. Until the early 20th century, laudanum was sold without a prescription and was a constituent of many patent medicines. Today, laudanum is recognized as addictive and is strictly regulated and controlled throughout most of the world.Laudanum is known as a ""whole opium"" preparation since it historically contained all the opium alkaloids. Today, however, the drug is often processed to remove all or most of the noscapine (also called narcotine) present as this is a strong emetic and does not add appreciably to the analgesic or anti-propulsive properties of opium; the resulting solution is called Denarcotized Tincture of Opium or Deodorized Tincture of Opium (DTO).Laudanum remains available by prescription in the United States and theoretically in the United Kingdom, although today the drug's therapeutic indications are generally confined to controlling diarrhea, alleviating pain, and easing withdrawal symptoms in infants born to mothers addicted to heroin or other opioids. Recent enforcement action by the U.S. Food and Drug Administration (FDA) against manufacturers of paregoric and opium tincture suggests that opium tincture's availability in the U.S. may be in jeopardy.The terms laudanum and tincture of opium are generally interchangeable, but in contemporary medical practice the latter is used almost exclusively.