How does your friend know he has parasites? Please don't believe everything Hulda Clark wrote. She died of cancer. Her acolytes make all kinds of excuses why she couldn't save herself, but a lot more people who she treated died of cancers too, some that could have been cured by conventional treatment.
Humaworm has a great parasite cleansing program. They have a forum here, with a REAL naturopathic doctor who is there to help people.