Adjunctive melatonin therapy has the potential to improve tardive dyskinesia symptoms in patients with schizophrenia, according to a meta-analysis in the Shanghai Archives of Psychiatry.
“Tardive dyskinesia can occur in up to 20% of schizophrenia patients receiving long-term antipsychotics,” researchers wrote, “and is associated with considerable personal suffering and social and physical disabilities.”
To gauge the effectiveness of adjunctive melatonin in patients with schizophrenia and tardive dyskinesia, researchers conducted a meta-analysis of 4 randomized controlled trials involving 130 patients. A previous meta-analysis included only 2 randomized controlled trials, so investigators in this study tapped both English and Chinese databases, since the latter is not widely used outside of China.
Adjunctive melatonin was superior for reducing the severity of tardive dyskinesia, according to the new meta-analysis, although the improvement did not reach significance level.
The potent antioxidant properties of melatonin, or an ability of the neurohormone to modulate dopaminergic pathways associated with movement disorders, could explain how melatonin is able to ease tardive dyskinesia, researchers wrote.
The overall evidence quality of tardive dyskinesia symptom improvement in the meta-analysis was low, according to the GRADE (Grades of Recommendation, Assessment, Development, and Evaluation).
“If melatonin is shown to be effective in tardive dyskinesia, it may be a readily accessible and affordable option,” researchers wrote. “However, future higher quality and larger randomized controlled trials are needed to confirm these results.”