The 72 hour claim
You will see online that cortisol takes 72 hours, or three days, or up to six weeks, to clear after a stressful event. It is repeated so often it sounds like settled fact. It is not.
Here is what we can say honestly.
- Cortisol is a stress hormone. It rises when a dog faces something stressful and it falls again after.
- Studies that measure cortisol in dogs, usually in saliva, tend to find levels move back toward normal over minutes to hours after a single stressor. Exact timing depends on the dog, the event, and how the sample was taken.
- Chronic stress is different. A dog who is stressed day after day can show a changed baseline.
- We do not know of solid research showing a fixed three day clearing time for ordinary pet dogs.
So treat the 72 hour figure as folk wisdom. It may point at something real, which we cover next, but it is not a measured fact.