Are ssris and nsris negatively, positively, or neutrally charged chemicals? will a chelator that binds only to posetive charges interact with them?

That is difficult: To answer but consider their ability to move through the brain, full of electrical conduction via ions. These ions do not affect the ability to of the molecule to land on and effect the protiens that effect reuptake. Chelation, for whatever reason you are doing it, should not affect this though ask the chelation person how it affects antidepressants. Gd luc.

Complicated: Medical evidence only supports the usage of chelation therapy for the removal of heavy metals (lead, mercury, arsenic) from the body. There are no other proven benefits of chelation therapy. Ssris are large molecules with molecular weights over 300. It has become a trend to do chelation therapy for reasons other than the treatment of heavy metal toxicity, don't buy into it.