Why does my dog only have diarrhea at night? Could it be their diet or stress causing it?

Okay, let me walk you through what happened with my dog and this weird nighttime diarrhea issue. It was really baffling for a while there, and honestly, pretty worrying and messy.

Watching and Wondering

So, the whole thing started kinda suddenly. My dog, Max, would be perfectly fine all day long. Energetic, eating normally, solid poops outside during his walks. Like clockwork, though, sometime in the middle of the night – usually between 2 and 4 AM – I'd hear that tell-tale whining or pacing. I'd rush him outside, and boom, diarrhea. Not just soft stool, but full-on liquid explosions. Then, come morning, he'd seem fine again! It was maddening.

First thing I did was just observe. I needed to figure out if there was a pattern I was missing. I started tracking everything:

• What time he ate his dinner.
• Exactly what he ate all day – kibble, any treats, chews?
• When he got his treats, especially in the evening.
• His water intake, especially before bed.
• Any signs of stress or anxiety later in the day.
• Anything unusual happening in the house at night? New noises?

I kept a little notebook for a few days. Dinner was usually around 6 PM. He got his usual kibble. Sometimes he'd get a dental chew around 8 PM while we watched TV. No obvious signs of stress, he seemed pretty chill.

Trying Things Out - My Process

Armed with my notes, which didn't show anything super obvious, I started trying to change things one by one. This was key – only change one thing at a time, otherwise you don't know what actually worked (or didn't).

First attempt: Dinner time. My first thought was maybe dinner was too close to bedtime, or just sitting too long. So, I shifted his dinner earlier, to around 4:30 PM. Waited a couple of nights. Nope. Still had the nighttime emergency runs.

Second attempt: The evening treat. That dental chew he got around 8 PM was the next suspect. It was the only thing he consistently ate later in the evening. Maybe it had an ingredient that just didn't agree with him after sitting for hours? So, I cut it out completely. No evening treat at all. Waited a few nights... Bingo. The diarrhea stopped.

Just to be sure, after about a week of no issues, I tried giving him the dental chew again one evening. Sure enough, that night, around 3 AM, we were back outside dealing with diarrhea. That pretty much confirmed it for me.

Figuring It Out - The Culprit

So, in our case, it turned out to be the specific dental chew we were giving him in the evening. Why it only caused issues hours later at night, I can't say for sure. Maybe something about his digestion slowing down overnight meant that particular ingredient sat longer and caused irritation? Who knows. All I knew was, stopping that specific chew stopped the problem.

He gets a different kind of chew now, much earlier in the day, and we haven't had a repeat of the nighttime diarrhea since. It was a process of careful watching and trying things methodically. Every dog is different, of course, and if this happens to your dog, checking with a vet is always a good idea, especially if it doesn't clear up fast. But for Max, thankfully, it was just a matter of figuring out that one problematic evening snack.