INTRODUCTION: Recently, neurological abnormalities in methcathinone users have been attributed to manganese. We report similar toxicity in three patients following the use of a mixture similar to methcathinone: potassium permanganate, ephedrine, and aspirin. CASE REPORTS: Three teenagers (15 to 19 years old) presented with extrapyramidal abnormalities and movement disorders following chronic intravenous use of a mixture known as "Russian Cocktail". All three patients had multiple movement disorders. One patient had normal blood manganese concentration (<19 microg/L) and MRI. The other two had elevated blood manganese (2100 microg/L and 3176 microg/L) and MRIs showing bilateral symmetric hyper-intensities on T1-weighted-images in the dentate nucleus, subcortical white substance of cerebellar hemisphere, globus pallidus, and putamen. Abstinence and treatment with EDTA, levodopa, and para-aminosalicylic acid was associated with decreasing blood manganese concentrations and subjective improvement, but no change in objective findings. DISCUSSION: The "Russian Cocktail" likely contains manganese as a result of the oxidation of ephedrine by potassium permanganate in water acidified by acetylsalicylic acid. We believe that manganese with the possible contribution of methcathinone caused the neurological impairments. CONCLUSIONS: Three toxic substances have been made into a mixture administered intravenously, similar to methcathinone. Our patients learned of this mixture, called "Russian Cocktail", from their friends. The toxicity from repeated use of this mixture is one of extrapyramidal abnormalities and movement disorders. Standard therapies were unsuccessful in reversing the clinical toxicity.