The first step in treating a patient with Parkinson's disease (PD) and psychiatric symptoms is ensuring that the patient actually has PD. No disease-modifying treatments or neuroprotective drugs exist for PD. Treatments include levodopa; dopamine agonists such as pramipexole, ropinirole, and apomorphine; monoamine oxidase inhibitors such as seligiline and rasagaline; and glutamatergic antagonists such as amantadine. Psychiatric symptoms are highly prevalent in PD, but are often unrecognized and undertreated, and are easily missed if not specifically investigated. Psychotherapy is evidence based treatment for many idiopathic psychiatric disorders, and does not cause side effects or worsen motor symptoms. The specific psychiatric disorders in Parkinson's disease are: mood disorders, anxiety disorders, psychotic disorders and cognitive disorders. The other psychiatric symptoms in Parkinson's disease are: delirium, sleep disorders, and sexual disorders.