L-Theanine in the Adjunctive Treatment of Generalised Anxiety Disorder: A Double-Blind, Randomised, Placebo-Controlled Trial

Publication date: Available online 8 December 2018Source: Journal of Psychiatric ResearchAuthor(s): Jerome Sarris, Gerard J. Byrne, Lachlan Cribb, Georgina Oliver, Jenifer Murphy, Patricia Macdonald, Sonia Nazareth, Diana Karamacoska, Samantha Galea, Anika Short, Yoann Birling, Ranjit Menon, Chee NgAbstractPartial or non-response to antidepressants in Generalized Anxiety Disorder (GAD) is common in clinical settings, and adjunctive biological interventions may be required. Adjunctive herbal and nutraceutical treatments are a novel and promising treatment option. L-theanine is a non-protein amino acid derived most-commonly from tea (Camellia sinensis) leaves, which may be beneficial in the treatment of anxiety and sleep disturbance as suggested by preliminary evidence. We conducted a 10-week study (consisting of an 8-week double-blind placebo-controlled controlled period, and 1-week pre-study and 2-week post-study single-blinded observational periods) involving 46 participants with a DSM-5 diagnosis of GAD. Participants received adjunctive L-theanine (450-900mg) or matching placebo with their current stable antidepressant treatment, and were assessed on anxiety, sleep quality, and cognition outcomes. Results revealed that adjunctive L-theanine did not outperform placebo for anxiety reduction on the HAMA (p = 0.73) nor insomnia severity on the Insomnia Severity Index (ISI; p = 0.35). However, LT treated participants reported greater self-reported sleep satisfaction than placebo...
Source: Journal of Psychiatric Research - Category: Psychiatry Source Type: research