Chelation is like a fridge magnet. The stronger the magnet the better it holds up postcards. The stronger the chelator the better it holds onto a toxic metal.

Life is like a box of chocolates is Tom Hanks famous line in Forrest Gump. Using that concept of analogy, chelation with a cation exchange chelator is like a fridge magnet. You want that the magnet holds up postcards well, so you want a strong magnet. In magnets this is a strong magnetic force, in chelators it is stability constant. Too weak a magnet (eg:DMSA for Gd) and the post card falls off the fridge (redistributes), but you want a fridge magnet that is strong enough to hold up a thick post card, or corners of two postcards. Medium strength fridge magnet may be able to hold up one, but not two (EDTA). Whereas a stronger magnet can hold up a thick post card, and even two postcards (DTPA) so little chance of them falling off, redistributing. The strong holding up of the post card is shown by magnetic force, the strong adherence of chelator to Gd is stability constant.

So life is like a box of chocolate, I hate to say for GDD patients that box contained a number of yucky ones. Chelation is like a fridge magnet. I will play more with this analogy in future blogs.

Richard Semelka, MD