Nux Vom 200 at bedtime, every night for five nights after stopping the drug will help to detoxify the body. Then you may need to give remedies according to the symptoms experienced at this time. Each case will have different symptoms according to their individuality. Avena Sativa and passiflora mother tinture may be taken 5 to 10 drops in a spoonful of water three times a day. It will help to take away craving. Separate the two mother tinture dosages by an hour.
All the best. Post his progress and we will try to help. When he has the craving, if he knows it will not get any worse, it is helpful.