Opium has been used for thousands of years as a medicine and for religious or ritual purposes. Early medical texts already describe opiates as narcotics. The main active substance in opium is morphine. This substance became popular as an anesthetic drug since the 1850s. It has also been used against coughing, as a medicine for fever and diarrhea. Morphine is still widely used today. Since the discovery of morphine, a lot of research has been done to discover an anti-pain medication that is less addictive. This led to, among other things, heroin.Because opium and heroin were widely available since the nineteenth century, opium addiction became popular. At the beginning of the twentieth century, a legal attempt was made to stop this addiction, unfortunately this had little effect. In opiates, the pharmacologically active substances are morphine, codeine and thebaine alkaloids. Alkaloids are natural constituents that are available in different forms and contain nitrogen. Various attempts have been made to synthesize alkaloids. That is why the book distinguishes between opiates (natural and formed from opium) and opioids (synthetically produced anesthetics). Morphine and heroin are injected directly into the blood stream although Codeine and opioids are often taken orally. Once opiates are in the body, they can quickly pass through the blood-brain barrier. For example, only a few seconds after administration, heroin has already reached the brain. This works differently with morphine and codeine. Because of their solubility in water, only twenty to thirty percent reach the brain, while the rest is excreted again. In the liver, morphine and heroin are both converted to morpine-6-glucuronide, which is an active metabolite. Morphine and its metabolite have a half-life of 1-3 hours, so it works relatively long as an anesthetic...