Dr Seidel Snacks For Comfort Travel Are Full-Value Dog Snacks Containing Ginger And Tryptophan, Increasing The Comfort Of Travel For The Dog And Its Owner. Ginger Alleviates Nausea And Prevents Vomiting. Tryptophan – A Precursor Of Serotonin (The ‘Happiness Hormone’) Reduces Muscle Tension And Susceptibility To Stress.