Sleep Disruption in Ageing Pets

Disrupted sleep, including nighttime pacing, vocalising and reversed day-night cycles, is one of the most distressing changes owners report in ageing dogs and cats, and it has several distinct causes ranging from pain to canine cognitive dysfunction to sensory loss. Identifying which is driving the disruption changes the treatment completely.

Causes of Sleep Disruption in Older Pets

Canine cognitive dysfunction syndrome involves beta-amyloid plaque accumulation in the brain similar to human Alzheimer's disease, disrupting neurotransmitter signalling and circadian rhythm regulation, which commonly manifests as increased nighttime activity, vocalisation and disorientation while daytime sleep increases to compensate. This day-night reversal is one of the most reported symptoms in affected dogs.

In cats, hyperthyroidism increases metabolic rate and can cause restlessness and nighttime vocalisation independent of any cognitive change, while osteoarthritis pain in both species often intensifies overnight when the pet has been still for hours, making it harder to find a comfortable position and triggering repeated waking and repositioning.

Cognitive Dysfunction and the Sleep-Wake Cycle

• Pacing, wandering or vocalising during the night without an obvious trigger
• Increased sleep during the day, sometimes appearing disoriented on waking
• Staring blankly at walls or into space during waking hours
• Difficulty settling into a comfortable position before finally falling asleep
• House soiling occurring specifically overnight rather than during the day

Cognitive dysfunction, pain and sensory loss frequently coexist in the same older pet, so a dog that paces at night due to arthritis pain may also show early cognitive changes, meaning a single-cause explanation is often incomplete and each contributing factor needs its own assessment.

Pain and Discomfort as Hidden Drivers

There is no single test for cognitive dysfunction; diagnosis relies on excluding other medical causes, including bloodwork to check for hyperthyroidism, kidney disease or diabetes, alongside a validated cognitive dysfunction screening questionnaire completed by the owner covering disorientation, interaction changes, sleep-wake cycles, house soiling and activity level.

A pain assessment, including orthopaedic examination and sometimes a trial of analgesic medication, helps determine whether discomfort is contributing to nighttime waking, since pain-related sleep disruption often responds within a week or two of adequate pain control while cognitive dysfunction does not.

Diagnostic Approach to Nighttime Disturbance

Management is layered according to which contributing causes are identified, often combining medication, environmental change and a consistent daily routine.

• Selegiline or propentofylline for confirmed canine cognitive dysfunction to support neurotransmitter function
• Melatonin or trazodone, used under veterinary guidance, to help re-establish nighttime sleep
• Adequate analgesia for underlying arthritis or other sources of nighttime pain
• A consistent daytime activity and light-exposure schedule to reinforce normal circadian rhythm

Restoring a Stable Sleep Routine

Increasing physical and mental stimulation during the day, including short structured walks and food puzzle toys, helps reduce excessive daytime sleeping that contributes to nighttime wakefulness. A nightlight in the pet's sleeping area can reduce disorientation-related waking in pets with concurrent vision changes.

Keeping a sleep diary noting waking times, vocalisation and any apparent triggers helps the vet distinguish patterns consistent with pain, cognitive change or a medical cause such as needing to urinate more frequently, and tracks whether interventions are working over subsequent weeks.

When to seek help urgently

• Sudden onset of severe disorientation or apparent blindness alongside sleep changes
• Seizure activity occurring during or around sleep disturbances
• Sleep disruption accompanied by significant weight loss or vomiting
• Sudden aggression or distress during nighttime waking episodes

Sleep disruption in an older pet usually has an identifiable, treatable component, and your vet can help separate cognitive, painful and medical causes rather than assuming the change is simply untreatable ageing.