What you are speaking of is rapid detox. You are sedated while you are given shots of naltraxon or an equivalant. It is over in 24 hours. It costs about $3000.00. The success rate, I understand is very low even for
a drug treatment. Most people still have withdrawals for
several days following the treatment.
At 800mg a day, you can consider yourself a hard core user taking extreme doses. Methadone may be an option for
you since I believe your life to be in danger.