Relapsing forms of MS such as relapsing-remitting MS (RRMS) and progressive-relapsing MS (PRMS) are characterized by unpredictable episodes, called relapses or exacerbations, of acute worsening of neurologic function which may involve new symptoms or a worsening of older symptoms. With RRMS, relapses are typically followed by periods of partial or complete recovery, or remission.
For an attack to be consider an MS relapse, it must meet the following criteria:
- New symptoms appear or old symptoms of MS become worse
- Episode of new or worsening symptoms lasts for more than 24 hours
- Symptoms of the relapse do not occur within 30 days of a previous relapse
- There must be no other explanation of the symptoms
Many people with MS who are heat sensitive may experience a temporary worsening of symptoms when the weather is very hot or humid, sunbathe, get overheated from exercise, or take very hot showers or baths. Some people may notice that their vision becomes blurred when they get overheated—a phenomenon known as Uhthoff's sign. Even a slight elevation in core body temperature of one degree can cause a temporary increase in MS symptoms.
These temporary changes in symptoms are called pseudoexacerbations which look like and act like real relapses, but are temporary and do not indicate disease activity or progression. Realize that when we talk about pseudoexacerbations, we are certainly speaking of very real symptoms as there’s nothing “fake” about the experience; it is just temporary. Common triggers that may cause a pseudoexacerbation include infection, especially urinary tract infection, stress, pain or fatigue, exposure to heat or cold, premenstrual syndrome, or certain medications.
It is also possible to have symptoms which are due to an underlying medical condition, such as a thyroid problem, a vitamin deficiency, migraine headaches, or anemia, rather than MS; but it can be hard to tell the true cause. For instance, you might think that vision changes are related to your MS, but in fact they may be caused by migraines.
To avoid pseudoexacerbations, try to eliminate exposure to possible triggers. To treat a pseudoexacerbation, treat infections, reduce stress, use strategies to keep cool (or warm), and discuss potential underlying medical problems with your doctors.
Treatment of MS relapses
The intensity of a true relapse or exacerbation may be mild or severe enough to interfere with a person’s ability to function at home and at work. Relapses are unpredictable and no two exacerbations are alike. Symptoms vary from person to person and often from one relapse to another.
Relapses often result from active inflammation in the central nervous system which damages the myelin and disrupts the transmission of nerve impulses. This inflammation may be seen on MRI scans as swelling or active lesions. However, not all relapses result from new lesions, nor do new lesions always cause detectable symptoms or a relapse which is one reason why neurologists typically do not rely upon MRI scans to determine the presence of a relapse.
Not all exacerbations require treatment. Mild sensory changes (numbness, pins-and-needle sensations) or bursts of fatigue that don’t significantly impact a person’s activities can generally be left to get better on their own. For severe exacerbations (involving loss of vision, severe weakness or poor balance, for example), which interfere with a person’s mobility, safety, or overall ability to function, most neurologists recommend a short course of high-dose corticosteroids to reduce the inflammation and speed relief of relapse-related symptoms more quickly.
The most common treatment regimen is a 3-5 day course of intravenous Solu-Medrol® (methylprednisolone), also called IVSM, or high-dose oral Deltasone® (prednisone). Most people are able to receive IV treatment on an out-patient basis, either at home or in a doctor’s office. Depending on the physician’s preference, the patient’s condition, and the length of the treatment, the IV steroids might be followed up with a 1-2 week tapering dose of oral steroids. Corticosteroids, however, are not believed to provide long-term benefit against the disease.
A non-steroidal alternative treatment for an acute exacerbation is H.P. Acthar® Gel which contains the hormone ACTH (adrenocorticotropin). Acthar can be self-injected subcutaneously (under the skin) or intramuscularly (into the muscle) by the patient, friend, family member, or healthcare professional.
Corticosteroids and Acthar should always be taken under a doctor’s supervision. Possible side effects include stomach irritation, elevation of blood sugar, water retention, restlessness, insomnia, mood swings, and increased risk of infection. As steroids can stimulate appetite and increase water retention, follow a low-salt and/or potassium-rich diet and watch your caloric intake.
Although most patients tolerate treatment well, doctors may prescribe medications to help the person sleep, reduce anxiety, and minimize stomach discomfort. Report any new symptoms or complications you experience during or after treatment for a relapse.
Be aware that it may take days, weeks, or even months to recover from an MS relapse or exacerbation. The best thing you can do for yourself during a relapse is to rest and allow your body time to heal.