The Stress Duo: Adrenaline and Cortisol in Your Dog
When we think about stress in dogs, we often picture the “bad” kind: barking, pacing, shaking, or reactivity. But stress is not always a bad thing. Just like in people, stress is part of how dogs experience the world. A little bit of stress can actually be helpful. It can fuel excitement, sharpen focus, and even build resilience. The real key is understanding what happens in your dog’s body during stress and why recovery time matters so much.
At the center of it all are two big players: adrenaline and cortisol.
Adrenaline: The Spark
Adrenaline (also called epinephrine) is the body’s immediate response to stress or excitement. It is released within seconds when your dog spots a squirrel, hears fireworks, or sees the agility ring for the first time that day.
Adrenaline does things like:
Increase heart rate and breathing
Dilate pupils
Send blood to muscles so the body is ready for quick action
It is fast, powerful, and clears from the body fairly quickly once the event is over. This is why you often see your dog “crash” after an exciting event. That spark burns hot and then burns out, leaving the body ready for rest.
Cortisol: The Fuel
If adrenaline is the spark, cortisol is the fuel that keeps the fire going. It takes a little longer to kick in but lasts much longer.
Cortisol:
Keeps blood sugar elevated for sustained energy
Temporarily dampens pain and inflammation
Keeps your dog on high alert for hours (sometimes even days)
Here is the important part: cortisol does not vanish once the event ends. Research shows it can take anywhere from 24 to 72 hours for levels to return to baseline after a big spike.
How They Work Together
Think of adrenaline and cortisol as teammates.
Adrenaline is the spark that kicks off the fight or flight response.
Cortisol is the fuel that keeps the dog in that heightened state if the stressor does not stop right away.
Recovery is the cool down. Adrenaline drops quickly, but cortisol lingers.
That is why your dog may still seem edgy or on guard the day after a vet visit, a trial, or a reactive outburst.
Why Recovery Matters
Stress itself is not the enemy. Play sessions, competitions, or big hikes all create what we call “good stress” (or eustress). The problem comes when stress keeps stacking up without recovery time. That is when cortisol builds up and the body does not get a chance to reset.
Signs your dog might need more recovery time include:
Short fuse or irritability around triggers
Trouble settling or sleeping
Stress-related stomach issues
Slower progress in training
Chronic stress has been linked to immune suppression and behavior challenges in both people and dogs.
Helping Your Dog Recover
Think of recovery like a rest day for athletes. Dogs need a chance to bring their systems back into balance after a stressful or exciting event. Some simple ways to support recovery include:
Slow, sniffy walks at your dog’s pace
Chewing or licking enrichment
Quiet time or naps without interruption
Predictable routines that create a sense of safety
The Bottom Line
Adrenaline and cortisol are not bad. They are natural, built-in parts of your dog’s biology. But without enough recovery, they can stack up and make life harder for both you and your dog.
So, the next time your dog crashes after a big day, remember: that is not laziness, it is biology. Rest, decompression, and gentle activities are not just nice extras. They are how your dog’s body and brain reset.