Pet Naturals Calming Chews for Cats offer fast-acting calming support for thunderstorms, vet visits, traveling and separation anxiety. Thiamine (Vitamin B1) helps manage stress and reduce irritability. L-Tryptophan plays a key role in the production of neurotransmitters (i.e. serotonin) responsible for sleep and relaxation. L-Theanine supports calming & relaxation through the production of calming amino acids. Lemon Balm is an herb in the mint family shown to have a calming affect on cats. These naturally sourced ingredients are packed into a tasty chicken liver-flavoured chew that cats love!