Cooling therapy is a unique form of therapy used by people with multiple sclerosis (MS). Small decreases in body temperature may lead to relief of some MS-related symptoms. Cooling methods range from the simple to the complex. The use of cooling suits for MS was introduced in the United States in the early 1990s.

Although warming may produce a worsening of symptoms, cooling may lead to improvement in symptoms. This cooling effect has been observed with cold baths or exposure to cold air. This beneficial response to cooling is the basis of cooling therapy.

Different Ways to Keep Cool

Simple measures include:

  • Taking cool showers or baths
  • Sitting near a fan or air conditioner
  • Using an ice pack
  • Wearing cotton clothing
  • Avoiding warm environments
  • Drinking cold liquids

More sophisticated approaches utilize garments, such as vests, that produce body cooling. Cooling garments may be “passive” or “active.” Passive garments, which use ice packs or evaporation for cooling, are simpler and more portable, while active garments, which actively circulate coolants, appear to produce more effective cooling.

More sophisticated cooling methods are currently under investigation. Specialized “heat extraction devices” involve placement of one hand on a cold surface within a chamber that is under a vacuum. These devices take advantage of the large volume of blood that circulates just under the skin on the palm of the hand.

Heat and Multiple Sclerosis

The effect of heat on MS symptoms has been known for years. Worsening of symptoms with small increases in body temperature, which occurs in 60% to 80% of people with MS, was first described in the late 1800s by Dr. Wilhelm Uhthoff. The “hot bath test,” developed in the 1960s, was one of the earliest methods for diagnosing MS. With this test, which is no longer used, people suspected of having MS were placed in a hot bath and assessed for any worsening of symptoms. A similar process may be observed early in the course of MS when the only noticeable manifestation of the disease is a symptom, such as weakness, numbness, or visual blurring, which occurs only in situations that increase body temperature, such as exercise, sunbathing, fever, or warm showers or baths.

The Benefits of Cooling to People with Multiple Sclerosis

Small research studies indicate that cooling produces improvement in MS symptoms. One of the older studies, reported in the late 1950s, showed that a temperature reduction of as little as 1°F led to noticeable benefits.

A rigorous study of cooling in MS was reported in 2003. In this relatively large study, 84 people with MS and heat sensitivity were evaluated for both the short- and long-term effects of cooling. The cooling apparatus used in this research involved technology developed at the National Aeronautics and Space Administration (NASA). For the short-term component of the study, low-dose and high-dose cooling were administered for 1 hour. For the group that received high-dose cooling, a small amount of improvement was noted in multiple objectively measured parameters, including walking speed and visual abilities. Less notable changes were observed with low-dose cooling. In the long-term portion of the study, the effects of daily cooling over 1 month were examined. By self-assessment, people believed they improved in fatigue, strength, and thinking processes during this time.

Many other studies have yielded positive results for cooling in MS. Taken together, these various studies indicate cooling may produce improvement in a wide range of MS symptoms, including:

In general, the use of cooling garments is well tolerated. There may be a feeling of discomfort when cooling begins. Some people report that handling the garments is cumbersome.

It is important to keep in mind that individual variation occurs in the amount of cooling and the extent of benefit. Some people exhibit little or no reduction in body temperature with cooling. In approximately 10% of people with MS, a paradoxical response may occur, and symptoms may actually worsen with cooling therapy.