Sudden Acquired Retinal Degeneration Syndrome (SARDS)

Sudden Acquired Retinal Degeneration Syndrome, often referred to as SARDS, describes a pattern in which a dog loses vision over a period of days to weeks, often quite rapidly, due to changes in the light-sensing layer at the back of the eye. The retina stops working properly despite the eye itself appearing structurally normal on initial examination. The underlying cause remains poorly understood, though immune-mediated processes are among the possibilities considered. Owners typically notice that their dog has become hesitant to move in dim light or unfamiliar spaces, may bump into objects, or seem suddenly uncertain in environments they previously navigated with ease. The change can feel abrupt—a dog who was seeing normally one week may appear functionally blind the next. Many dogs otherwise seem well in themselves at the time vision loss is noticed, though some owners observe changes in thirst, appetite, or energy in the weeks surrounding the onset. This page explores what signs tend to appear and in what timeframe, what is understood about the processes that may lead to retinal dysfunction in SARDS, how the condition is investigated and distinguished from other causes of vision loss, and what approaches exist for supporting a dog living without sight.