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198419 tn?1360245956

Question of the Month (May ’13): Uhthoff’s Phenomenon (Heat Intolerance)


Wilhelm Uhthoff recognized the connection between heat and the worsening of MS symptoms back in 1890, and got this fun symptom named after him.  

Special thanks to Immisceo for requesting this month’s question.  She wants to know how the heat affects you and what creative actions you take as the temp rises to maintain your cool and functional ability.  So how DO you make sure ol’ Uhthoff doesn’t shut down your summer enjoyment?

Our Monthly Question focuses on a specific topic. There are no right or wrong answers -- we just want to hear about your experiences. Whether you are a veteran of this forum, are new here or have been lurking and waiting for inspiration - please share your thoughts.

Thanks again Immisceo for the timely question suggestion.  
Community members are encouraged to let a Co-CL (purple flower) know if there’s a question you’d like pondered in a future month.  

Thank you!
~Your community leaders
25 Responses
1831849 tn?1383231992
That ain't a flak jacket under my shirt in my avatar pic :-) It's my brand new cooling vest!

My heat intolerance typically manifests when I am exercising outside. The minute my core temp hits a certain point my left leg gets a mind of its own. If I push it too far then my nystagmus can join the fun.

I've tried a bunch of different things to mitigate the heat. Prior to the vest I've tried evaporative cooling neck wraps and hats. These really didn't work as they are no good in humid areas (shoulda read the product description!). I have also tried a cool-pack collar with a flap that extended to cover my upper spine. That was OK but still not great.

So now we have the vest. I tried it out last week during Walk MS. I had no problems at all, but it was neither hot nor humid :-) So school is still out.

I have learned that I am much more likely to have issues in humid environments rather than simply hot ones. Here in NYC area it is always humid. Last summer I went to the Canadian Rockies and did all kinds of hiking and biking. At altitude there is no humidity and, even though I got plenty hot and sweaty I had no problems.

5112396 tn?1378021583
Thanks so much for posting on this topic, especially with such a well-written question. I'd totally forgotten the proper medical term and never learned about its namesake!

I did indeed see your fetching cooling vest Kyle! So interesting about the hot versus hot and humid thing. Ireland? Humid. Sicily? Hot. So I've not had the double whammy yet, unless this thing was percolating far longer than I realise.

My specific angle on this is perhaps a little unexpected. Because I'm on a drug study, I have a neurological exam quarterly. Last autumn the prof was at ECTRIMS, so a colleague stepped in.

I suppose I got out my usual 'auto-pilot' for the exam and asked this other neurologist about Uhthoff's as I've never experienced it myself. This didn't compute to me as it seemed like everyone had it to some extent.

I will not pretend to recall his words verbatim, but my strong recollection was he indicated that heat intolerance tends to be there from the beginning if it's something you're going to have. If not, it doesn't tend to show up in future.

Of course, this doesn't strike me as likely, given the nature of the disease process. I keep forgetting to bring it up to my regular neurologist for clarification! I have my notebook ready for my next exam, but that's a couple of month's off yet.

Have any of you heard anything like that?  I do feel kind of weird about not ever experiencing this classic symptom/collection of worsening old symptoms. Perhaps Kyle's on to something there with it being a bit climate-specific and I've just lucked out there.
645800 tn?1466864555
I never knew the term for heat intolerance but boy do I have it. I am bothered by heat year round.  

I have tried the ICE PACK type of vest but I can't tolerate the cold from it. I'm in the process of trying to find a good PHASE CHANGE type of vest to see if it will help me.  Since it only goes down to 58 degrees I don't think I'll have a problem of it being TOO cold.

I didn't developed the heat intolerance problem until about 10 - 12 years after my MS started. And it has gotten progressively worse over the years. Hopefully it won't get any worse as I'm already at the point that anytime I am exposed to temperatures over about 73 my symptoms start to go crazy.

So how do I deal with the heat?

First off I keep my bedroom at 60 degrees year round. Yes even in the winter I have the AC in my bedroom running. That way if the heat in my home starts to get to me I have a place to cool off quickly.

I also keep a fan running that blows on me while at my computer in the living room. You would be surprised at how much a desktop computer generates while it is on. Without the fan the area near my computer quickly raises to over 75 while the rest of the room is only 70.

Sleeping has been the worst time for me as I don't wake up if I get too warm. Normally your body temperature drops when you sleep, but not me. Mine goes up. So that 60 degree bedroom comes in handy. To get the real effect of the cold bedroom I sleep under a very light blanket like they give you in an ER if you are cold. I wear nothing to bed and keep the area from my knees down to my feet uncovered. That way the excess heat in my body is being directed to my legs and feet where the cold air cools me off.


Avatar universal
I'm not sure if it's proper for me to chime in seeing I haven't been diagnosed but I am finishing up a bout of ON and boy does that eye get blurry when I exercise. That is what ultimately got me the referral from the optometrist to the neuro-optomologist. I described to him how when my body temperature went up my vision went down. He knew right away. I notice it less now, however, as the eye has improved.
Avatar universal
Not diagnosed, but MS or whatever else, heat definitely makes things worse.  I take my shower too hot and I'm seeing double, shaking all over, legs feel like jello with lead, etc.  

A few things have helped so far.  When I get overheated inside and it's cold out, I can just step outside for a bit.  Like, too hot of a shower, too hot from exercise or getting too active cleaning the house, etc.  As long as I don't wait too terribly long, it helps.

Another thing that helps is drinking ice water.  Showers are the bane of my existence.  Too cool and it feels cold to my skin in areas my nerves are all out of whack, and if I let me toes get too cold my Raynaud's acts up.  Too hot and we all know how that goes.  So I keep a glass of ice water right outside the bathroom so that as soon as I'm done I sit down and drink my ice water.  I also can't leave my hair wrapped up turban style in my towel like I used to while I get dressed and do my make up.  It almost locks the heat in.  

I guess the ice water must cool me down from the inside.

But, I have noticed that if I let myself get too hot for too long.  Or even just a little hot for too long, like doing 45 minutes of exercise or heavy duty house cleaning where i"m really getting my heartrate up, then even after cooling down I feel awful.  It takes a nap and than just taking it easy the rest of the day.  
5112396 tn?1378021583
Thanks Dennis. Such good information and insight! That puts to bed that little fantasy of mine. But now I can be perhaps a bit smarter about the situations I put myself in instead of having a (perhaps misunderstood) fallacy that I was heat invincible knocking around in my noggin.

Funny; as I settle into my third year of this, I'm growing a lot more confident and prudent about the way I read signs from my body. The first year I attributed EVERYTHING to MS. Second year (because I'd had no relapses and *no one* can maintain that level of hyper-vigilance indefinitely) I attribute NOTHING to MS. My little denial phase.

Year three is all about becoming smarter about the amount of proportionate time I invest in monitoring myself and my body. I've finally formed a MAYBE pile and (hope) I'm growing a bit savvier about what is or isn't of note. Hearing you say it wasn't an issue from the get-go helps me refine that pile and hones my sub-conscious MS watch-dog. Thanks again, Dennis!
1831849 tn?1383231992
I tend to differ with your substitute neuro about heat intolerance having to be present at the onset. I've had MS for 22 years and my heat intolerance has developed over the last 2.

Prior to that I had about the same level of heat intolerance as anyone. If I got hot, I got hot. The changes to my vision and control of my left leg, when hot, are relatively new symptoms.

1760800 tn?1406757051
I too find my intolerance is to humidity rather than the heat -  I vacationed in St Martin and was worried how I would handle it.  Sat on the beach every day at least 4 hours of it in the sun and no issues -  I live in Maryland and we too are very humid -  Last summer we had several weeks where it was only 80 degrees but between 90 and 100% humidity.  My legs were worthless.  My foot drop in increased and no matter of cooling off helped -  just had to wait out the humidity.

Avatar universal
I have it bad.  Even walking or any activity when it's not hot outside raises my core body temp and causes me to become immobile (I am normally able to walk unaided).  It happens very quickly even if the sun is just on my back for a short period of time.  My vision goes blurry, then dim and my legs go limp, I have to sit or lay down and I become so confused I can't gather words to speak.  This is a problem because I can't explain to those around me what is happening and have such little warning.  I once had a partial seizure from the sun being on my back though my legs were in a pool and I felt cool and comfortable.  I have found that in an emergency situation like this, I pour cold water over my trunk/core and that seems to speed up the recovery process.  If I'm out, at that point I don't care if I'm dripping wet!  I avoid being in these situations at all costs, but I have still been caught off guard at times because it happens so quickly and it doesn't have to be hot outside.  You can only imagine how I have to avoid being outdoors when the weather is hot.
198419 tn?1360245956
Excellent techniques!

I really don't know if I have it to the extent of others.
But, it does zap my energy - especially the humidity. Initially, I'd just go inside for some airconditioning, but found that the return to the heat makes me completely worse (where I'd experience spasms like jumping in my legs).  

So, I don't do that anymore. I try to adjust to it - and stay in it. In the summer is keep a plastic water bottle with me when I know I'm going to be out in it long periods. The cool mist helps me alot. As does the cold water (someone mentioned that too). It cools my core.  I may go into the shade for a few to cool down instead of seeking a drastic temperature change inside.  

Any other contributors?
4907540 tn?1361980455
Recently been diagnosed with MS and i find when i have a very warm not hot shower afetrwards i have a tingling sensation in my left fingers and left toes..

Not sure how i will be with hot weather as in the UK we are just coming in to summer..so it will be interesting..

But i do notice that i can't tolerate a hot shower any more and after i have done an hour of exercise i find that my left side feels weaker than it used to.
1337734 tn?1336238191
I definately  have heat intolerance but like Kyle and Tracy, I am much more effected by humidity. I actually consider humidity to be my kryptonite!  Last summer  I needed to spend 2 separate weeks in south Forida where it was extremely hot an humid. It sent my body into such a major relapse that I am just beginning to slightly recover from. :(

Now that summer is approaching, I will do all I can to keep my body core cool.
I really try to limit the time I spend outside in hot, humid weather. I keep the central air conditioning on in my house 24/7. I swim in my pool every day which is great excersise and also cools my whole body down.

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