The three main reasons for any addiction are ignorance, ego and dependence. If you ask people why are they smoking?
Some will say that they were ignorant about its side effects (ignorance)
Others will say that it gave them a status in the society (ego)
And the rest will once they started, they can’t leave it and are now dependant on it (dependence).
The treatment of ignorance is based on education the principle of hearing (suno), listening (samjho), understanding (jaano) and action full of wisdom (karo).
Ego can only be treated by proper counseling. The principles of counseling are well described in Bhagavad Gita and involve 18 sessions over a period of time.
Dependence treatment involves early detoxification followed by counseling and education.