That itchiness is what's called Cholestatic pruritus. It is caused when, due to poor liver function, waste products get into the blood stream. It is mild form of jaundice. Urine colour may also change.
When the liver is obstructed and waste products back up into the blood stream it causes itching. This may have happened to you temporarily during the liver-flush. Rather than the liver filtering the blood the kidneys have to step in; not good long term.
However, the itching also occurs when an obstruction is cleared and toxins are pulled out from the skin.