Is flushing before a fast a neccessity?

Hi everyone,
I am planning a juice fast with the aid of psyllium husks(my very first one, mainly for weight loss and to get me on the track of eating healthily) but was very worried about doing the liver flush. It seems like such a long drawn-out process which is putting me off doing the fast. Is it a neccessity that I parasite & Liver Flush before AND after my fast? What are the benefits of doing one? Are there any dangers of me fasting for a long period of time and not doing one?

Looking at the ingredients I am also struggling to find somewhere where I can buy them, therefore I will try the "Classic Coke" Liver Flush and Gallbladder Flush as ingredients are easier to get hold of, if it's a neccessity to fasting and I will reap some benefits.

Any advice or support greatly welcomed. Many thanks.