Information, Symptoms, Treatments and Resources

Heat Sensitivity & MS

Feeling beat in the heat? 

Almost all people living with Multiple Sclerosis have problems with heat sensitivity symptoms. Normally, heat exposure does not cause permanent damage, but it can leave you feeling debilitated and unable to function fully.

We often have options whether we are going to be in the heat   - we choose to go on that vacation to the beach or take the children to the amusement park.  We can also often hide indoors during the worst of the season and avoid the worst of the heat.  But many times there isn't a choice and we must go to work, mow our lawns, sit through an extra innings Little League game or work in a place that is not air conditioned. 

There are a number of strategies the experts recommend to help control the effects of heat.   The following are from my notes of several recent MS talks on the web, via telephone and in person, in addition to my own observations and common sense.

First, we need to understand that most people with MS are heat sensitive because of the scars in our central nervous system.  Where we have demyelination even in the spots that are repaired by our own system, those areas do not insulate the nervous system as well as the original myelin coating.  Increases in our body temperature can cause an almost immediate change in our reaction to heat.


What is a normal body temperature?  It fluctuates widely, but normal is generally considered within a degree of two either side of 98.6 degrees Fahrenheit.


Heat exposure can cause previous known symptoms to be reactivated or new symptoms to appear.  The good news is these symptoms don't cause permanent damage, but nonetheless can put you into misery for some time.


We also know that often People with MS have trouble regulating their body temperature and the sweat glands don't work like they were intended.  We need extra aids to help our body adjust to the heat.


There are internal and external heat sources, many of which can be somewhat controlled or altered.  Internal sources of heat can come from infections (fever), spicy food and hot beverages.  Menopausal hot flashes are an excellent example of an internal heat source that cannot be easily regulated.


Medicines can also cause fluctuations in how our body functions, so be sure to review your drugs and their side effects with your doctor/MS nurse.



Hydrate.  Yes, I know the temptation to withhold liquids because of bladder problems associated with MS, but don't do it.  We need liquid and lots of it, especially during the dog days of summer.  So drink and then drink some more.


Drink plenty of cool drinks, preferably water.  Limit the amount of caffeine you consume.  Sodas and juices don't quench thirst as much as water.  Even though that ice cold beer tastes great going down, it can help to elevate your temperature. 


Now is the perfect  time to indulge your inner child and eat frozen treats such as popsicles - they serve a dual purpose and cool and hydrate simultaneously.



Be strategic about your exposure - do your errands that require you to be outdoors early or late in the day.  Avoid the mid-day heat- specifically between the hours of 10 and 2 when the sun is at its most direct exposure.  Humidity can also play a big role in how your body reacts to the heat.   If it is going to be the record-setting day  perhaps you need to rethink your plans .



NASA may be an agency of the past now that the shuttle has been grounded, but one legacy left from space exploration is the technology developed to cool astronauts and its transfer to our own use here on Earth.   It was a collaboration between MSAA and NASA in 1994 that led to the acceptance of cooling as an essential part of handling the heat for people with MS.

There are several types of cooling, including active cooling, which involves either batteries or electricity to power the cooling unit.  Evaporative cooling, which allows the body to cool by evaporation can also be extremely effective. You can create your own evaporative systems with a misting bottle and a fan or breeze. 



Pre-cool your body by taking a cool/cold shower or do an ice water plunge with your feet and hands to cool your core temperature before venturing out.  The benefits of precooling your body can last up to two hours in regulating your internal temperature.



Dress appropriately with light color clothing.  Select clothing made of cotton or visit the sporting goods section and purchase athletic clothes that have the property to wick moisture away from the body.    Jockey has a line of underwear that claims to cool the body by up to 3 degrees and I am waiting to hear from someone who has actually tried these to report if they work.


Invest in cooling garments.  These can be the simple neck scarves or wrist bands that you presoak in water or the more complex cooling vests. MSAA and MSF both offer cooling garment programs to provide them at no cost if your income eligible.   


There are many commercial options available for these specialized clothing choices - you can find many options by searching the internet which wil turn up numerous options.  Confused by the choices?   Check out for honest consumer reviews. 


You can also create your own cooling garment by moistening the clothes you are going to wear - a wet t-shirt will create your own evaporative system that will help to control a rise in your body temperature.





No, we can't fool Mother Nature, but we can alter it a bit with some planning.


Take frequent breaks if you are doing something active outdoors or indoors - give your body the chance to cool down.  We still need to exercise - we need to keep moving, even if it is summer.  Take cool down breaks and don't push yourself to the point of being overheated.  Avoid getting to that point of no return.


Carry a chilled gel pack in your pocket.  Nothing says "cool down" any quicker than strategically placed ice packs. You can buy mini-sized reusable ice packs that are designed to fit in children's lunch boxes.  These are the perfect size to slip discreetly into your clothes and will provide 2-3 hours of cooling effect.


If you are driving some distance before you will be out of the car, consider getting a small portable cooler that plugs into the adaptor plug in your car (formerly known as a cigarette lighter outlet!). These units can help to keep the gel pack frozen/chilled for longer periods of time. 


Create your own shade by carrying an umbrella.  Think of all the pictures you have seen of exotic places where the women carry an umbrella for shade - maybe it's time for those of us in the western cultures to adopt this practice. 


Simple activities such as meal preparation can create extra heat, so consider preparing your meal on the grill outside, or drag out that crock pot and cook that meal in one pot that you don't have to stand over and stir.   Consider making multiple meals at one time in the kitchen - freeze meals for future use, reducing the number of times you have to stand at the stove.





So many of us don't feel the need yet to take full advantage of accessibility opportunities, but summer is the time to get over that hesitance. This is the time to accept those things that can make our life easier.


Get that handicap placard and use it to park closer to your destination.  The extra distance you can save on the hot parking lot surface can make a difference when you can park closest to the door.    If you are going on vacation, even if you are flying, be sure to take that placard with you.  Law officials honor placards from other states. 


Something as simple as parking your car on a hot day in a covered spot or under a shade tree will help with managing the heat.  Your body will thank you if the car you are getting into is a few degrees cooler from being parked in the shade.


On a recent vacation trip to Florida, we visited Disney World.  Even though we came by airplane, I remembered to take my parking placard.  At Disney, this pass was good to park in their special handicapped rows, and we were in the second row of parking from the main entrance.  This kept us from having to park in the outer lots and stand in the heat waiting for their tram to come.  This simple move easily cut out an extra 15 minutes or so of exposure to the heat.


Don't be afraid to ask for accessible seating if you are at a public venue. Usually these seats are a bit more spacious and more air can circulate, keeping you cooler; their locations are normally better situated to aisles and exits, and take less time to get to your seats.  Again, those extra steps and minutes can make a huge difference.



I know this was a lot to get through - it took me several hours to compile these notes into some order that might make sense and be of help.  I hope there is something in here that you can take away and use immediately to help with the heat.  

Develop your own cooling program - trial and sample products and techniques until you find the ones that work best for you.   Rely on the experiences of others to help you design your program - an excellent website that has tips and much more is  Be sure to check them out.

Take control and don't be beat by the heat .



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