In Sheltons experience he did not believe or endorse "forcing measures" and that includes enemas and the Liver Flush as well, because they only provided extra problems for the body.
He believed, as I do, in a "Laissez-Faire" approach in healthcare and recovery, and that the body decides in its own wisdom what is the very best option.
In your shoes I would try "Intermittent Fasting" (IF): one day of feeding and the next day of fasting, and repeat on alternate days: this will greatly accelerate the healing and cleansing process if you are unable to do an extended fast.