I've done 5 flushes so far and threw up o the third one but still got decent results.
I think that it is possible that you could have been reacting to the mixture of apple juice and grapfruit juice in the same flush. I normally don't have a hard time with grapefruit juice but decided to forego the epsom/grapfruit mixture and tolerate the epsom/water just to see what happened. I had absolutely no nausea. Could be coincidence but it was also the first fluch where I felt a noticable surge in my energy level.
Were I you I'd use either the apple or the grapefruit, not both...see what happens.