I work with Dr Yu in St. Lois who has a ton of experience with parasites. He finds it almost impossible to treat without meds-herb and homeopathics.
The other issue that makes it hard-to impossible-is if you have a dental issue wearing you down. Hard to get rid of parasites.
He has a website and several articles on parasite-you may want to read them. FYI- he is an MD-in the US Army for 20 years now reserve and treats parasites ever single week