Brief Answer: Yes, Detailed Answer: Hi, Thanks for your query. Yes, Phenobarbital can be used to overcome the withdrawal effects of stopping the Benzodiazepine like Alprazolam (Xanax) taken for long. Also Phenobarbital does detoxify considerable amount of the drug as it induces enzymes which are involved in detoxification of many such drugs. But the dosage of Phenobarbital has to be formulated by considered facts like -The indication for Xanax -Duration of Xanax -Side effect profile in you of Xanax and - Clinical examination findings. Do consult your treating doctor for a better formulation and safe dosage. Also you will need n hand written prescription for the same. Wish you good health. Regards,

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