DA agonists such as pramipexole (Kurlan et al., 2012) and the selective monoamine oxidase B inhibitor selegiline (Buoli et al., 2016; Akhondzadeh et al., 2003), commonly used to treat Parkinson’s disease, have also been found to be effective for ADHD by enhancing DA neurotransmission at the synapse. Here, MAOB is linked to Parkinson disease.