Citicoline as Adjuvant Therapy in Parkinson's Disease: A Systematic Review.

Purpose: Parkinson disease (PD) medications are not readily available in all countries. Citicoline increases dopamine synthesis and inhibits dopamine uptake. This systematic review aims to synthesize current existing evidence on the efficacy of citicoline adjunctive therapy in improving PD symptoms.

Methods: An extensive literature search of Scopus, Embase, PubMed, Cochrane Library, and Google Scholar was conducted for articles published on or before December 31, 2019. The studies were screened and selected by 2 independent reviewers. We included all studies that explored the efficacy of citicoline as an adjunct therapy in PD.

Findings: A total of 7 studies (2 crossover, 3 randomized controlled, and 2 open prospective studies) were included. Despite the varied outcome tools, this review found that patients with PD who were taking citicoline had significant improvement in rigidity, akinesia, tremor, handwriting, and speech. Citicoline allowed effective reduction of levodopa by up to 50%. Significant improvement in cognitive status evaluation was also noted with citicoline adjunctive therapy.

Implications: Citicoline adjuvant therapy has beneficial effects as an adjuvant therapy in patients with PD. However, due to the heterogeneity of the studies, there is a need for more high-quality studies.