Why do P&B shakes make me itchy and symptomatic?

I feel like crap a few hours after drinking a psyllium and Bentonite clay shake. 1 tsp of each with a couples glasses of water.

I get really itchy, headache, unable to relax/sleep. I don't understand it in the slightest. It never used to do that when I tried them about a year and a half ago. Tweet