how long can a person be miserable after stopping methadone treatments?

i have a freind that took methadone for 6 years and then went off of it 5 mil at a time now they are done and it has been about 14 days when will the mood swings stop?

: http://alcoholdrugstreatment.info/how-long-can-a-person-be-miserable-after-stopping-methadone-treatments