It is a chemical substance that changes the physical, emotional or behavioral state of the person taking it.

It is the harmful or hazardous use of psychoactive substances such as alcohol and illicit drugs.

It is the use of a drug for which it was not intended or using a drug in excessive quantities.

It is a state of physical or psychological dependence on a drug.

It is the scientist recognize that genetic predispositions to drug abuse exist.

It is the influence of home environment, especially during childhood, is a very important risk factor.