Lead is considered a key element in causing autism disease in children due to the pollution of this dangerous element to human. The aim of this research is to obtain a chemical compound with the effect of inhibiting the oxidation of lead ions on the brain that causes the autism disease. Cyclic voltammetric technique was used to study the effect of interferences between lead ions with selected elements such as Mn(II), Mg(II), Zn(II), Ca(II), PO 4 -3 and Co(II) in blood medium. Multi wall carbon nano tube (MWCNT) which was modified with glassy carbon electrode (GCE) was used as a working electrode sensor in cyclic voltammetric method. The results showed that the oxidation and reduction current peaks of Pb(II) ions in the blood medium appeared at -0.2 and -0.8 V respectively. It was found that Co(II) ions had a significant effect on the Pb(II) ions in blood medium as anti-oxidative reagent by reducing the anodic current peak of Pb(II) with five folds and enhancing the cathodic current peak. But other ions such as Mn(II), Mg(II), Zn(II), Ca(II) and PO 4 -3 reduced both redox current peaks of Pb(II) in blood medium. It means that Co(II) ions acted as a good anti-oxidative reagent in blood medium which reduced the effect of lead ions on brain cells by the blood stream. Hence, cobalt compounds could be used as drugs for treatment of the autism disease in children.