(Virbac) Anxitane Chewable Tablets contain L-Theanine (Suntheanine) to help keep pets relaxed and calm. L-Theanine is an anti-anxiety amino acid found naturally in green tea. The L-Theanine in Anxitane was produced using a patented enzymatic process called Suntheanine to achieve 99.5% pure L-Theanine. Only Suntheanine achieves this level of purity and relaxed neurological activity. Anxitane promotes relaxation in pets exhibiting nervousness, anxiety, or fear and helps pets cope with changes in their environment. In order to achieve the full benefit from Anxitane, the minimum recommended course of treatment is 2 months. L-Theanine.