Users of the illegal stimulant cocaine frequently choose to introduce the drug into their systems by inhaling (snorting) it through their nasal passages. When used in this manner, cocaine enters the bloodstream by passing through linings in the nasal interior called mucous membranes. People who inhale cocaine through their noses put themselves at a clear risk for developing forms of nasal damage that include a perforated septum, bleeding, a chronic allergy-like condition called rhinitis, and degradation of the nasal sidewalls that can lead to lifelong facial deformity.
Polydrug use is a highly hazardous form of substance abuse that involves either simultaneous use of two or more drugs, or use of two or more drugs within a narrow timeframe. In addition to illegal drugs such as 
Any drug that causes physical and psychological harm and that leads to addiction is dangerous. Addiction to any substance is a disease and one that is difficult to beat. Even addictive behaviors are very challenging to give up; it is the nature of the disease. However, there are chemical differences between drugs that make some harder to quit than others. Researchers have looked into just how different substances are in terms of addiction and created a scale. One such initial study conducted in the UK controversially placed alcohol and tobacco ahead of some 
People living in the Andes Mountains in South America have been using 