The word 'drugs' conjures up a host of fears and evils, and it is true that the addictive drugs heroin, cocaine, crack, ecstasy and marijuana, generally have majorly negative effects on the human nervous system. Their possible side effects include memory loss, paranoia, neurological damage, social maladaptability, depression and death. Occasionally they can be prescribed under expert supervision.
The two drugs names as the most dangerous by the United Nations are nicotine and alcohol, and both have an effect on the brain and the body.
Both these drugs cause death, and society is in an interesting position of manufacturing, marketing and selling them, while the government collects large revenues from their taxes. Observe popular culture (film, television and print media) and see the prevalence of smoking, alcoholic consumption and usage of drugs.
So why are drugs being discussed on the Creativity Web? Because drugs affect the mind. I'm not a drug user, but there are many instances of people reporting "enhanced creativity" following consumption of peyote or magic mushrooms. Although drug users may report positive things, I believe the long term effects are negative, and there are other methods to achieve the same result, such as exercise.