It seems we all may experience twinges, prickles, and outright stabs, at some times, when cleansing...and most anywhere in the body. (Would you believe fingers and toes, and at the extrem right and left sides of the waist?!)
I have no idea what causes them.
Through all my reading in this forum, I see that R.G. suggests to do plain liver flushes BEFORE parasite cleansing, and/or one week, or more, AFTER...with only one exception.
That was to a person who was in extreme difficulty. I may remember wrongly, but he may have suggested that person stop the Humaworm for a short period, while they flush...so that the flush itself would be a 'plain' one, I guess.
You would need to consider what you, yourself, need. Since you have experience flushing (I don't), you will know what you prefer...what seems reasonable to you.
Likely it depends on the severity of the twinges, as well.
I wish I knew something more definite to suggest.
Keep us filled in on developments, won't you?