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Why has my older dog started weeing in the house?

by | May 24, 2026 | Latest Monthly Newsletters, Pet Care

“My senior dog has started weeing in the house overnight, when they always used to hold it all night – why?”

If your doggo previously aced Toilet Training 101 but something has recently changed, it could be due to a number of wee-sons (sorry, we couldn’t help ourselves…)

Here are some potential causes of wayward wees in older dogs.

Urinary incontinence

This is when a pet leaks urine involuntarily, and it most often happens when they are lying down or sleeping. However, some pets will also dribble urine as they’re walking, or just after doing a wee.

The most common cause of developed urinary incontinence in mature female dogs is known as USMI (urethral sphincter mechanism incontinence). This is due to a hormone-responsive weakness in the muscles around the urethra, making the pet unable to effectively hold urine in their bladder.

Other causes of developed urinary incontinence can include spinal diseases or injuries, prostatic diseases in male dogs, or urinary tract infections, bladder stones or bladder masses.

Toileting behaviour changes

If your senior pet seems able to hold their urine but is then consciously toileting in the wrong area, it could suggest:

  • A health issue causing increased bladder discomfort, such as a urinary tract infection, bladder stone or bladder mass.
  • Increased overall wee volume, which can occur with health issues such as kidney disease or diabetes.
  • An unwillingness to use their designated toileting facilities, which can result from:
    • Anxiety, e.g. if a negative incident happened while they were toileting previously
    • Physical difficulties reaching their toileting facilities, e.g. reduced mobility or vision
    • Dirty or otherwise unsuitable toileting facilities
  • Forgetting their normal toileting behaviours, which can occur with age-related cognitive decline (doggy dementia).

The bottom line? If your pet’s toileting habits have changed, we’d recommend a consultation with one of our knowledgeable vets, so we can “get to the bottom” of their issue pronto!