Why is my senior dog holding her pee all day, only going at night?

It is likely just a habit that he urinates after drinking. Senior dogs can hold urine for up to 14 hours if healthy to not at all if incontinent. I am afraid there is no set time. You may want to take Pepper in to your veterinarian for a senior wellness exam. He may be suffering from a UTI or prostate problem should he appear sick.

At her age there are several things it can be. Your vet can collect a urine sample to check for a urinary tract infection. They can always draw some blood to check her kidneys and blood sugar and for Cushings disease. All these can cause an increase in drinking and urination which will lead to accidents. If all of that is normal, than she may be getting incontinent and they have medication for that also!

He could have a urinary tract infection or a medical condition that makes him urinate more. The best thing would be to have your vet run a urinalysis and blood-work to rule out medical causes. If the lab-work is normal then you should make sure you take him out as late as possible before bed time and you could also limit the amount of water he drinks late at night.

I can't think of anything wrong with what he is doing. Is it possible that it is harder for him to squat on the pee pad inside? Maybe it shifts around or is in a tight location? As dogs age, they can develop arthritis that makes it uncomfortable to posture to urinate and defecate and sometimes you see these changes. It may be a good idea to have him checked over by a vet.

There are many possible reasons for incontinence and a basic physical exam can be useful to check for arthritic changes which may be contributing and treatable. If no obvious reason is found euthanasia may be worth considering as invasive tests and work up although providing diagnosis may not uncover treatable causes and quality of life can quickly slide in such patients

I'm sorry you're dealing with this frustrating issue. If needing an early morning bathroom break is a change, I'd recommend starting with a vet visit to make sure she doesn't have a UTI, bladder stone, skin infection, or even organ function problem etc. Those issues all can all increasing the amount of water she's drinking, making her need to go out in the middle of the night. If there is no medical issue, then it's a house training problem, which is difficult at her age. Usually using a crate to re-house train as if she were a puppy is the most effective course of treatment to deal with this.

She is probably suffering from urinary incontinence, a common condition in old female dogs, take her to the vet and they will first rule out a urinary infection then they will start her on a medication for urinary incontinence.