Each individual case is different, but I had my immune system checked with a number of different tests and they found nothing wrong with it and that it's functioning properly. I'm on ParaGONE for my parasite cleanse along with a liver and Colon Cleanse and I'm getting 'stuff' out every day. I'm also feeling a little bit better each week. My naturopath has me on these cleanses and says it's important to stay on them for several months until I feel completely better and have eliminated everything from my body that's hurting me.
Usually, people that have chronic issues do have something wrong with their immune system. But I don't see how you can 'fix' your immune system without eliminating the crap in your body that's causing it to be stressed.
If I were in your shoes, I would work on 'fixing' my immune system WHILE cleansing. Just my opinion.