During rapid detox, patients are kept under sedation and injected with a cocktail of drugs to accelerate and intensify the withdrawal process. After a few hours, the worst of the withdrawal pains are over, and patients undergoing the procedure over a weekend will be well enough for work on Monday morning.
If Suboxone works as well, is easier to get off of and you can take home a month's supply at a time - why would anyone still choose methadone???