Complexing agents are used to treat heavy metal poisoning for over sixty years. One of the first of these compounds was developed in the forties of the past few years hundreds of UK British Anti-Lewisite, which was used as an antidote to the arsenic and chlorine-containing chemical warfare agent Lewisite.

In the fifties of the last century, the complexing Dimercaptopropan- sulfonic acid (DMPS) was synthesized in the former USSR and used clinically. DMPS is available under the name Unithiol in Russia.

DMPS has been approved in Germany since 1997 under the name Dimaval. Studies have shown that it is highly effective in treating acute and chronic mercury, arsenic and lead intoxication.

Clinical research has been u. A. Carried out in Germany, the United States (University of Rochester), in Iraq, in Bangladesh and in the Philippines. Recently Unithiol is available again.