I did Clark's program and it worked very well. Others have had good luck with the other programs on this forum and Dr. Sutters Liver-Flush and others online. Since I also have constipation and sprue I take a magnesium laxative the evening before the flush to make sure my magnesium levels are adequate and to uncongest the small intestine so that when you take the grapefruit/olive oil mixture it won't be blocked from entering the small intestine. Often the Liver-Flush is a two day process for me. When it is time to take the OG mix if I feel too congested or ill I don't take it and the next day I dont eat solid food or any fats/oils then do the two ES doses and take the OG at 10 PM. The first several flushes were very difficult but I persisted and finally began to pass thousands of stones. If I felt nausea after taking the O/G I learned to sit up and put my tongue on the soft palate and stroke downward from the base of my sternum then continue that for a while after laying back down. I would have to do that several times during the night, anythime I felt nausea or had reflux.
Hope this helpa.
I did a search for 'Blastocystis herbs' so there are herbal treatments. I think that Blasto is one of the organisms that grows in a biofilm which protects it from treatment. You may want to use an enzyme mixture to digest away the biofilm.