I have no personal experience with the using the clays internally.

I do recall a warning that came out on green clay, not too long ago, but I cannot find it now on Google.

There was a poster on OBT who knew a person who gave green clay to her
child with Tourette's and it supposedly detoxed the child. But I really cannot endorse it myself.

The only internal clay product that we had here was taken off the market.
Kaolin-pectin and Diasorb were taken off until they filed a new drug application for efficacy and safety, and the companies declined to do so. Prior to that Kaolin was grandfathered into FDA stats and rules.(like Robitussin was) So Kaopectate today is different inside...it is now the same as Pepto Bismol.

Clays contain minerals, and it is conceivable that they can be contaminated with lead or arsenic like natural dolomite can. They are also very adsorbant and will bind drugs and prevent their absorption. So if anyone on medications uses clay, they may lose effectiveness. So the two issues: Safety and Effectiveness are basically unproven at this time.