Multiple sclerosis relapses (also known as flares, attacks, or exacerbations) are when the patient experiences new disease activity. This could be a reoccurrence of old symptoms or new symptoms such as problems with vision or difficulty walking or balancing. The severity of relapses can range from very mild to very severe depending on the patient.
To be classed as a relapse or exacerbation, the incidents need to last at least 24 hours and be separated from the previous relapse by a month. Relapses can last for days, weeks or even months. They are caused by inflammation of the central nervous system (CNS) which damages myelin and disrupts the messages from the brain to different parts of the body.
According to the National MS Society, those who have relapse-remitting multiple sclerosis (RRMS) will have relapses followed by long periods of remission (where there is no new disease activity). However, those in remission will often find they still have ongoing MS-related symptoms.
The treatment and management of relapses depends on how the body is affected and to what severity. Some mild relapses may not need any treatment, just rest. Others may require treatment using intravenous corticosteroids to lower inflammation and reduce the length and severity of the relapses.
If the patient is unable to have intravenous corticosteroids or they are ineffective, their doctor may prescribe H.P. Acthar Gel (ACTH) which is a hormone injection designed to stimulate the adrenal cortex gland to produce aldosterone, cortisol, and corticosterone. Around 10 percent of MS patients who experience severe relapses will require a plasma exchange.
Following a relapse, MS patients may need to undergo rehabilitation which may involve various health professionals such as cognitive specialists, physiotherapists, occupational therapists, and speech-language therapists.