The invention relates to combinational treatment using a monoclonal anti-alpha-synuclein antibody and an additional medicament. The antibodies can be used for treating a synucleinopathy such as Parkinson's disease (including idiopathic and inherited forms of Parkinson's disease), Diffuse Lewy Body Disease (DLBD), Lewy body variant of Alzheimer's disease (LBV), Combined Alzheimer's and Parkinson disease, pure autonomic failure and multiple system atrophy together with another medicament of the invention.