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L-Tryptophan for Dogs With Anxiety

| Updated September 26, 2017

Tryptophan deficiencies have been implicated as a cause for increased anxiety and aggression in dogs. Supplementing diet with L-Tryptophan is a natural way of reducing those feelings of anxiety, improving your dog's behavior.


Tryptophan is a neutral amino acid that exists naturally in your dog's body and is essential in small amounts for a healthy diet. It aids in healthy digestion and serves as the precursor to serotonin, a neurotransmitter associated with healthy, calm emotions and self-control.


L-Tryptophan was banned as a dietary additive for humans in 1989 after a contaminated batch from Japan caused illness. However, it is still available with other supplements for pet use.


Studies show that dogs with tryptophan deficiencies are more likely to show aggression, depression and moodiness. Thus, dogs that show signs of aggression or anxiety are often treated with L-Tryptophan, which reduces aggression and increases calm behavior.


Many medications for anxious dogs cause liver and kidney damage when long-term use is necessary. Since L-Tryptophan is a natural amino acid, it can improve your dog's behavior without concern of organ damage.


L-Tryptophan should not be administered without veterinary approval because it can react with some medications and cause side effects such as vomiting and diarrhea.