Accutane Survivor: Gastrointestinal Problems??

Hi.
I took Accutane about 10 years ago, and I've been having some gastrointestinal problems since then, such as bloating, loose stools. I took some Antibiotics for 5 days about 1.5 years ago, and developed severe bacterial, candida, and parasitic infections. My acupuncturist thinks that the Accutane weakened my GI track; how does it do this?? What specifically does it do to your GI track. I have been able to heal the bacterial and candida issues, but it took about a year. The parasites, specifically worms, however, are still a huge problem. I cannot really get on with my life until this is not an issue anymore. Also, I have severe problems with dehydration and constipation no matter how much water I drink. Is this due to the Accutane?? I've been on the anti-candida diet for about a year now, and I live a healthy life style.
If anyone can please explain to me how Accutane affects the GI track and what I can do to heal my GI track and get rid of the worms and lower the candida levels in my body, it would be much appreciated!!!!
Thanks!!
Seascapes