Hello Treatment response is a multifactorial result...no one method can give you sure shot guarantee of success..... Successful outcome depends on many things....if your brother is motivated for treatment or not...if not than in patient treatment is almost must... Secondly how good his tolerance is..does he create lot of fuss with slight amount of problem or he is ready to bear the side effects of withdrawal thirdly you have to consult a psychiatrist for it , and how much your psychiatrist is comfortable in OPD detoxification And last but not the least,,, depending on motivation you have to decide about rehab vs hospitalisation.....lower the motivation more is the need of rehab.....