Hello and welcome to Healthcare Magic. Thanks for your query.
I appreciate your concern for your friend. But it is not possible to suggest any treatment without knowing exactly what the substance of abuse is. The nature and severity of the withdrawal symptoms
also depend on the kind of substance.
I would suggest that you advise your friend to see a doctor for a proper evaluation and further treatment. Since you say that he feels overpowered by his addiction, he would need professional help to get out of it. It may not be necessary to have an in-patient rehab program; for mild cases of addiction, out-patient treatment can be effective. But it is important that your friend is motivated and co-operative for treatment.
Wish you all the best.
Dr. Jonas Sundarakumar