Hello, Codeine addiction should be quit gradually. It is best to detox in a medical environment so that withdrawal symptoms can be managed successfully. Codeine should never be abruptly stopped because it produces serious symptoms like extreme craving, insomnia, body-aches, vomiting, nausea, depression, etc. Codeine withdrawal may be physically agonizing and psychologically stressful so get him connected to a detox services center so that the withdrawal symptoms can be managed urgently and he is comfortable. Tapering off codeine may take time, from a few weeks to a few months. The user slowly adapt to having less codeine in their system, so the withdrawal is much less severe. Opiate substitutes, like Methadone or Suboxone, may be used in place of Codeine to taper off use. These help to calm codeine cravings and other withdrawal symptoms. These substitutes should not be used without medical supervision as they can be addictive. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Nupur K., General & Family Physician