I've been doing Dr. Schulze 's 5-day liver cleanse for years and used to breeze through them. Now for the past few years I've done them 3-4 times/year and get excruciating sick headaches by the first or second day, going from my brain stem up to my frontal lobes.
I hardly ever get headaches. I've had the same reaction on the rare occasions I've had a cold over the past few years and I attack the cold with the Dr. Schulze methods. I usually clear the cold out in 48-72 hours but the pain in my head is unbearable. I never use aspirin but times like this I'm tempted to take one because I'm on a liver cleanse right now and feel like hell.