Patient Blogs | Multiple Sclerosis
Heat Is My Enemy
photo of man with sweaty forehead

Three years ago, I set out one spring morning on my scooter to see some art. It was Open Studios in San Francisco, where artists open their workspaces to the public and talk to us about what they do. I love Open Studios, but this time my art adventure ended with an ambulance ride to the emergency room.

What happened? I got too warm. Weather most people would call “a beautiful day” caused my whole body to shut down.

According to the National Multiple Sclerosis Society (NMSS), most people with MS are “temperature-sensitive.” We don’t do well when our bodies get warm because our damaged nerves lose their ability to conduct signals. I am extremely temperature sensitive. Heat is my enemy, and on this day, heat won.

I live on the foggy side of SF, close to the ocean. I set off in the morning wearing sweatshirts because it was gray and cold out and I would be outside and on buses. In SF, we always dress in layers.

The art studios are mostly on the sunny, Eastern side of town, and as the day went on, the fog burned off and it got warmer. At first I didn’t notice I was getting weaker, and I waited too long to take off layers. I remember I was in a pottery studio when I realized I had a problem. My hands wouldn’t work well enough to control the scooter.

I tried to take my sweatshirt off, but it’s tight, and I was too weak to do it. Being warm also affects my brain function, so I wasn’t thinking clearly, and I decided to tough it out. The sensible thing to do would have been to ask someone to help me take the shirt off and maybe get me some ice to cool down, but I didn’t know anyone in the space.

Instead of asking for help, I rolled out to the bus stop, thinking I could wait in the shade. But there was no shade, and I kept getting warmer and weaker. The bus came; I got on, but it wasn’t much cooler inside than out. When it came time to get off the bus, my hands weren’t working. I couldn’t maneuver the scooter at all, and they had to call an ambulance. All the other passengers had to get off the bus and wait for the next one while we waited for the EMTs.

The medics checked my temperature and it was 102.1. That’s what caused my body to collapse. When I got to the ER, it turned out I was dehydrated and also had a urinary tract infection (UTI), of which I had been unaware. But none of that would have affected me so strongly if it wasn’t for the heat.

I cooled down in the ER for 4 hours while they gave me IV fluids, an antibiotic, and Tylenol. When my temperature returned to normal and the sun went down, I could go home, but I learned some important things that day.

Learning About Heat

According to the MS Society, even a very slight elevation of body temperature, like one quarter of a degree, can be enough to trigger heat-sensitive people, which is most of us. For me, even a small temperature elevation, like 98.8, can be enough to knock me out.

Doctors say that the symptoms of heat improve after you cool down. In my experience, they do, but it takes a long time. Don’t think you can just get in a cool space for a few minutes and be good to go. I find I have to be cool for a long time before my body feels recovered.

The good thing is that heat doesn’t make the disease process worse; it doesn’t cause new lesions of inflammation. Heat only increases symptoms temporarily. But “temporarily” can be a long time when you’re away from home or need to be up doing things. That’s why most of us feel a need to keep cool.

Things I’ve Tried to Keep Cool

Over the years, I’ve tried everything to keep cool. I’m writing this in the early morning, before the sun is up, with the windows open, sitting in a T-shirt. I’m not warm, and I feel good. My hands are flying over the keyboard. When it’s warm in here, I find it much harder even to type, or to sit straight, or to think.

At warmer times, I turn on an electric fan that’s about 2 feet away from me. That keeps me cool. We don’t use air conditioning because I have concerns about electricity costs and environmental effects, and we live on the cooler side of town anyway.

If you live in a warmer climate, which is most places, you might need air conditioning to be able to function. If possible, set up one air-conditioned room and stay in it most of the time when it’s hot. You don’t need to keep places cool if you’re only in them for a minute.  

I also avoid activities that warm me, like hot showers. I had to give up hot tubs, which I loved, and have to be very careful about aerobic exercise. For me, that meant giving up basketball in favor of water exercise in a cool pool. Swimming and water aerobics are treat exercises for heat-sensitive people. Exercising outdoors on warm days is risky; evenings and early mornings are better. Cool showers or baths before and/or after exercise can keep heat symptoms away.

What you wear makes a huge difference, as I found out at the Open Studios. I used to wear T-shirts and shorts, even when it wasn’t hot, just to keep cool. I also had some of the cooling clothes they sell to people like us and people who work in very hot environments. There are jackets and vests you soak and others you insert ice packs into. There are cooling scarves and hats that aren’t as heavy or as clunky as the jackets.

Not everyone agrees that extreme cooling is a good thing, even if it relieves our symptoms. An acupuncturist told me that in Chinese medicine, it was better for long-term health to keep warm. He may have a point because when I was wearing all the cooling clothes, my MS progressed rapidly.

In really warm environments, nothing will cool you down like a wet T-shirt and a fan. I think it’s crucial to stay hydrated when it’s warm. Popsicles are great, or cold fluids on a hot day. If I think I might get warm or might have a low-grade infection of any kind, I’ll take Tylenol before I go out to keep temperature down. That might just be a superstitious ritual I do, but I figure it can’t hurt.

Where you live is important. If a person with MS lives in Phoenix or Miami or rural Mississippi, they will probably wind up inside with the A/C on all the time. I chose my current residence because of cooler weather. I’m grateful to my wife for going along with this apartment because she prefers sun and has to go in search of it, but I need this kind of weather. If you can find a cooler climate than your current one, I’d say look into it if you can.

Of course, cool climates may be getting harder to find. I sometimes imagine global warming as a conspiracy against people with MS, but it’s the world we’re living in. We should do our best to manage the life we’re given.


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Photo Credit: Frederick Bass / fStop via Getty Images

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David Spero, RN

David Spero, RN

Diagnosed since 1989

David Spero, RN, became a writer and health coach after being diagnosed with multiple sclerosis in 1989. He writes books and blogs about living with chronic illness and the social causes of illness. A married father of two and grandfather of one, Spero is active in causes including health care, peace, and the environment. See his books; follow him on Medium or Twitter.

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