The link between your dog's emotions and their gut is direct and measurable. When your dog experiences anxiety or high excitement - whether from fireworks, visitors, car journeys, or even positive things like trips to the park - their sympathetic nervous system kicks in. This is the same 'fight or flight' response that humans experience.
What happens in their body
Stress hormones, particularly cortisol and adrenaline, increase gut motility (how fast material moves through the digestive tract). At the same time, blood flow is redirected away from the digestive system toward muscles and vital organs, as their body prepares to fight or run away. The colon has less time to absorb water, resulting in softer, looser stools. In some dogs, this process happens pretty quickly - sometimes within 20-30 minutes of a stressful trigger.
Things owners might notice
Some dogs consistently produce soft stools before vet visits, during thunderstorms, or when left alone. Others show this response during positive excitement, such as greeting guests or anticipating walks. The stools are typically soft but formed, rather than liquid diarrhoea, and often return to normal once the trigger passes.
Why all dogs are different
Sensitivity varies considerably. Dogs with naturally reactive temperaments, those with previous trauma, or breeds predisposed to anxiety (Border Collies, German Shepherds, toy breeds) often show stronger gut responses to emotional triggers. Puppies and older dogs may also be more prone as their stress regulation systems mature.
The role of the gut microbiome
Research shows that chronic stress can alter the balance of gut bacteria, potentially making the digestive system more reactive over time (1). Dogs experiencing frequent stress-related loose stools may benefit from consistent routines, gradual desensitisation to triggers, and maintaining a stable, simple diet that's easy on the gut.
If stress-related loose stools become frequent or severe, speak to your vet about behaviour support alongside digestive management.
References
- Mondo E, Barone M, Soverini M, et al. Gut microbiome structure and adrenocortical activity in dogs with aggressive and phobic behavioral disorders. Heliyon. 2020;6(1):e03311. Available from: https://pubmed.ncbi.nlm.nih.gov/32021942/
This content is for general information only and does not replace veterinary advice. Supplements and nutritional products are not licensed veterinary medicines. Always speak to your vet before making changes to your dog’s diet, supplements, or care routine.
