Sudden acquired retinal degeneration syndrome results in abrupt vision loss, typically within a matter of days to a few weeks. Some patients may have a more gradual (i.e.: few months) onset. Affected dogs have both hemerolopia (inability to see in bright light) and nyctolopia (inability to see in dim light or at night).

SARDS affects the thin-layered retinas which receive visual input and then transport this information to the brain via the optic nerve. In dogs with SARDS, the photoreceptors (rods and cones) and possibly the nerve fiber layers within the retinas undergo degenerative changes. The end result is complete blindness.