Lower the dose, or take a break for a few days and drink lots of water.

A couple of good things for an easier reaction time are ginger--either fresh, pickled, or capsules; and L-ornithine. It's a rough row to plow, but the worse you feel the better your cleanse is working. Good luck!

Im on day 9.5 of the clark protocol. The only discomfort I have had is cramping at times and constipation. I noticed when I have the cramping my next stool has a bunch of parasites. Im on the highest doses now and am feeling great. The first cramping was in my lower right side and kind of concerned me because this is the same feeling I had when I was about to pass a kidney stone. I ended up having a bowel movement with visible signs of a tapeworm. Im still passing worms and no longer feel bloated.
Hopefully things go smooth for you as well. Ginger ale is soothing for nausea and stomach pain. An asprin maybe for the headache.
Anyway,Im new to this cleanse and am about half way through it.

Good Luck