L-Theanine for Anxiety: Mechanisms and Adjunctive Role

<jats:p>L-theanine modulates glutamate receptors and increases GABA and glycine, offering a plausible anxiolytic mechanism. However, it lacks strong evidence as a primary treatment. Consider L-theanine for patients with ADHD plus insomnia, or those with mild anxiety requiring as-needed relief. L-theanine acts within 30 to 120 minutes and lasts five to eight hours, supporting 200–450 mg twice-daily dosing.</jats:p>