Secondary progressive multiple sclerosis

Secondary progressive multiple sclerosis (MS) is a form of MS in which symptoms are constant, do not improve, and may get increasingly worse. This is a result of steady damage to the nerves in the brain and the spinal cord.

The secondary progressive form of MS follows a phase known as relapsing-remitting MS, in which symptoms repeatedly appear or get worse, then improve. This cycle can repeat for many years before secondary progressive MS develops.