There are all kinds of different detox systems at health food stores, they may be able to point you in the right direction. I think most are a 30 days regimen. The company King Bio has some great products that are very safe. I've taken their Lymph cleanse recently. I had to try a few different brands before finding some that didn't make me feel like I got hit by a truck during the detox process or make me super constipated.
My naturopath doctor feels that twice a year, once you've gotten yourself cleansed initially, is good. Spring and Fall.
Best of luck!