| Tryptophan is an amino acid which is used to form serotonin. Low levels of tryptophan in the diet are thought to be linked to a fall in serotonin levels. This may have an affect on mood and can be used in alongside conventional pharmacological treatments, however care should be taken to look for any signs of serotonin syndrome. Studies have shown a reduction in behaviours related to stress and a decrease in signs of anxiety in cats supplemented with L-tryptophan<ref>Da Graca Pereira, G., Fragoso, S., L-tryptophan supplementation and its effect of multi-housed cats and working dogs. Proceedings of the 2010 European Veterinary Behaviour Meeting. Hamburg, 2010, 30-35.</ref><ref>Kato, M., Miyaji, K., Ohtani, N., et al. Effects of prescription diet on dealing with stressful situations and performance of anxiety-related behaviours in privately owned anxious dogs. 2012; 7:21-6</ref>Tryptophan can be added to the diet or is available at higher levels in some commercial diets. | | Tryptophan is an amino acid which is used to form serotonin. Low levels of tryptophan in the diet are thought to be linked to a fall in serotonin levels. This may have an affect on mood and can be used in alongside conventional pharmacological treatments, however care should be taken to look for any signs of serotonin syndrome. Studies have shown a reduction in behaviours related to stress and a decrease in signs of anxiety in cats supplemented with L-tryptophan<ref>Da Graca Pereira, G., Fragoso, S., L-tryptophan supplementation and its effect of multi-housed cats and working dogs. Proceedings of the 2010 European Veterinary Behaviour Meeting. Hamburg, 2010, 30-35.</ref><ref>Kato, M., Miyaji, K., Ohtani, N., et al. Effects of prescription diet on dealing with stressful situations and performance of anxiety-related behaviours in privately owned anxious dogs. 2012; 7:21-6</ref>Tryptophan can be added to the diet or is available at higher levels in some commercial diets. |