Anecdotal evidence suggests that some people with multiple sclerosis (MS) may experience night sweats and hot flashes in the evening. However, scientific research into MS and night sweats is limited.

To date, there are no scientific studies in which researchers have examined the severity or prevalence of night sweats in people living with MS. However, scientists have conducted research into the effects of MS on thermoregulation, or how a person’s body controls its internal temperature.

This article reviews research that discusses MS and thermoregulation, which involves sweating. It also explores how someone with MS can manage the effects of heat, treatment options for MS, and when someone should consider speaking with a doctor.

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Evidence suggests that MS may increase a person’s body temperature, but it may also interfere with regular sweating.

In a 2022 study, researchers reviewed some previous studies’ findings about MS and body temperature and sweating. They noted that some of these findings suggested the following theories:

  • People with MS may experience delays in sweating initiation and reduced sweating rate.
  • Individuals with MS may have higher sweat thresholds.
  • People with MS may have reduced sweat output in individual glands.

They also highlighted that an earlier study noted that one characteristic feature of MS is heat sensitivity.

As part of their own study involving people with MS who had COVID-19, the researchers noted that regular exercise helped increase blood vessel dilation and reduce their sweat threshold. However, the study did not specifically mention anything about night sweats.

An older 2010 study examined what researchers described as five themes of thermoregulatory dysfunction in MS, which are:

  • heat sensitivity
  • thermoregulatory effector responses
  • central regulation of body temperature
  • heat-induced fatigue
  • countermeasures to improve or maintain function during thermal stress

They found that previous research reported a reduced rate of sweating in people living with MS, but they also noted that heat stress may cause fatigue and worsening symptoms in people living with MS.

A small study from 2017 found that people living with MS experienced a reduced sweat rate compared with those not living with MS.

Reports of night sweats in people living with MS are anecdotal. In other words, it may be possible for a person living with MS to experience night sweats, but it may not be a common symptom of the condition. Alternatively, someone with MS may experience night sweats due to another underlying condition, such as menopause.

A person can take some steps to help manage the negative effects associated with heat. Some potentially helpful tips from the National Multiple Sclerosis Society include:

  • drinking cold fluids or eating ice pops
  • staying in air-conditioned areas whenever possible
  • wearing loose, light-weight clothing
  • exercising in a cool room or pool
  • using cooling products, such as vests, bandanas, or cool compresses
  • taking a cool shower or bath before and after exercise

Treatment for MS focuses on reducing the number and intensity of relapses and delaying the progression of the disease itself. There is no cure for the condition.

Some common treatments include:

A doctor may also work with a person on treating symptoms related to MS. These treatments do not modify the course of the disease, but they can provide relief from these symptoms.

Symptom treatments can vary based on what a person experiences. Interventions may include:

  • wearing glasses
  • using assistive walking devices
  • exercise and stretching
  • taking medications

Learn more about the best exercises for MS.

A person should consider speaking with a doctor about night sweats if they experience them. This symptom may not be a direct result of MS; another underlying condition may cause a person to sweat at night.

According to the United Kingdom’s National Health Service, menopause is a common cause of night sweats. Other common causes include:

People should consider contacting a healthcare professional if they are living with MS and notice worsening symptoms. This could indicate a relapse that may need additional treatment.

Research into MS and night sweats is limited. However, studies suggest that MS may cause heat intolerance and issues with body temperature regulation and sweat production. Additionally, there are anecdotal reports of night sweats in people with MS.

A person can take some steps to deal with the effects of heat, such as staying in an air-conditioned building on hot days, taking cool showers before and after exercise, and drinking cold beverages.

Other conditions, such as menopause, anxiety, or hyperhidrosis, can cause night sweats. A person should consider speaking with a doctor if they develop night sweats or worsening symptoms of MS. A healthcare professional may be able to recommend different treatments for MS or work out the underlying cause of a person’s night sweats.