If you have multiple sclerosis (MS), you may experience difficulty tolerating heat. Your symptoms may worsen when you’re overheated, so it’s important to know how to keep your cool.
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“With MS, the myelin or protective covering gets damaged either partially or completely, so it doesn’t cover the nerves,” says clinical nurse specialist Kathleen Schwetz. “So when people are exposed to different types of heat, and they are sensitive to it, their MS symptoms get worse.”
Some MS patients don’t have any problems. However, those who do may experience serious weakness, confusion and even fainting because of prolonged exposure to heat. If you reach that extreme limit, you need to seek immediate medical attention.
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Be aware of the sources of heat
Heat comes from two sources: internal and external. Internal heat — meaning your core body temperature — can rise if an infection raises your temperature and causes a fever.
Also, your core body temperature can rise from medicines used to treat MS, such as interferons. The side effects include flu-like symptoms and fever.
For an infection, see your physician for treatment. You also can take over-the-counter medicines such as acetaminophen or ibuprofen products to bring down your body temperature. Other options? Drink cool fluids, take a cool shower or rest.
Watch your exposure to heat from your environment
External heat sources that can cause increased MS symptoms start with hot, humid weather. If you are outside cutting the lawn, playing tennis or hiking in the middle of the day when it’s hot, for example, the effects of the heat may cause your MS symptoms to intensify. You may feel weak, numb and tingly and your vision may become blurry, Ms. Schwetz says.
Your temperature also may go up if you swim or exercise in a pool with especially hot water. Ms. Schwetz recommends that you only get into pools with a temperature in the low 80s or cooler.
What to do if you “feel the heat”
If you feel these symptoms, find a cooler setting, preferably where it’s air-conditioned. Drink cool fluids, put a wet towel around your neck and rest.
“If they go indoors and use whatever method to cool off and rest, within a few hours you should start to feel better,” Ms. Schwetz says.
Use common sense to protect yourself
Here are some suggestions from Ms. Schwetz to avoid overheating:
- Wear light, airy clothing, including a loose hat with a visor.
- Go for walks or exercise earlier or later in the day when it’s cooler; avoid the 10 a.m. to 2 p.m. midday sun.
- Drink cool beverages to stay hydrated.
- Take cool or tepid showers.
- Wear cooling collars, bandanas or vests or wrap a wet towel around your neck.
- Work in areas with air conditioning or fans; have at least one room in your home with AC.
- When you hike, run or exercise, go slow, pace yourself and know your upper limits of exertion.
Important to know
If you have MS, the National Multiple Sclerosis Society and Multiple Sclerosis Association of America can help you obtain fans and other cooling equipment. Ask your doctor for guidance. Your doctor can give you a standardized letter to your employers to let them know that you need a fan or AC and easy access to cool drinks.
“Most important, patients need to know that a heat intolerance incident is not a relapse of their symptoms, and it won’t make their MS worse,” Ms. Schwetz says. “But, a little bit of prevention and common sense goes a long way.”