Anxiety: An ignored aspect of Parkinson's disease lacking attention.

Parkinson's disease (PD) is a progressive neurodegenerative disease which affects millions of population worldwide. It is characterized by motor symptoms such as excessive tremor, bradykinesia, rigidity, postural instability and non-motor symptoms include neuropsychiatric complications like anxiety, depression, insomnia and cognitive impairment, orthostatic hypotension, sexual dysfunction and gastrointestinal complications. Treatment of anxiety in PD poses extensive challenge to global healthcare which makes it urgent to develop innovative treatment for the better management of the disease. The gold standard treatment by Levodopa provides symptomatic relief and its effect on neuropsychiatric complications like anxiety is elusive. Presence of anxiety worsens the condition and challenges therapeutic management of the PD. The in-depth analysis and understanding the molecular mechanism and pathophysiological pathways associated with the onset of anxiety in PD is essential. The disturbances in serotonergic, adrenergic and GABAergic neurons and hypothalamic pituitary adrenal axis play a significant role in the pathophysiology of anxiety. The drugs like Selective Serotonin Reuptake Inhibitors, tricyclic antidepressants and benzodiazepines are useful in the management of anxiety but due to severe side effects and progression of the disease it results in the failure of treatment. The present review imparts an insight in the management of anxiety in PD by understanding molecular mechanism and application of alternative treatment options which can enlighten the perception of researchers towards better therapeutic management of the disease.