Doctor’s Best L-Theanine Contains Suntheanine, Helps Reduce Stress & Sleep, Non-GMO, Gluten Free, Vegan, 150 mg (DRB-00197), 90 Count

Customers report that the supplement helps them sleep through the night and reduces anxiety without drowsiness, working within 30 minutes. Moreover, the product receives positive feedback for its effectiveness, with one customer noting it works well with caffeine, and another mentioning it's the purest form of theanine. Additionally, customers appreciate its focus-enhancing properties without jitters, improved mental clarity, and consider it good value for money. However, some customers report upset stomach as a side effect.