What herbs are in your bitter formula and what is GCG? Thanks!

I was wondering what do the bitters and GCG do? I'm in the middle if a parasite cleanse. Not Humaworm, I started it before I knew about Humaworm:( My parasite cleanse ends on the 11th. I was going to imedeatly start the MC. That will end on the 21st. And then I was going to do Clark's liver flush. (This is my first time to do any of these cleanses.) I didn't know about the bitters and GCG. Should I use them first? What is their purpose?

Thanks,
nuttymom