Cognitive dysfunction syndrome (CDS) is the canine equivalent of dementia, affecting the majority of dogs in their senior years. Early recognition, environmental support, and emerging pharmacological treatments can improve quality of life.
Canine CDS causes genuine suffering through confusion, disorientation, and disrupted sleep — experiences that are distressing even without the dog being able to communicate them. An elderly dog that wanders at night, vocalises without apparent cause, or fails to recognise familiar family members is experiencing a welfare decline that deserves active management rather than passive acceptance. Early intervention — before symptoms are severe — is more effective: environmental modification maintaining predictable routines, night lights to reduce disorientation, and cognitive enrichment that exercises neural pathways slows progression. Pharmacological management with selegiline, combined with dietary support, can stabilise or modestly improve symptoms in early-stage dogs. As the condition progresses, the welfare focus shifts to maintaining comfort — ensuring dogs are not confused and frightened, that they can rest adequately, and that the human-dog relationship provides comfort — until quality of life assessment indicates that euthanasia is appropriate.