Why is that once a person starts taking alcohol or drugs

Why is that once a person starts taking alcohol or drugs, it is difficult to get rid of this habit? Discuss it with your teacher.

It is difficult to get rid of alcohol or drugs once a person starts taking them because their repeated use lead to addiction. It increases the tolerance level of these substances in the body and the receptors respond only to higher doses of alcohol and drugs which in turn increases the dosage and it becomes difficult to get rid of the habit.