With the incredible heat waves this summer, Pharmacists Manitoba is warning the public that their medication might be the reason their heat tolerance is so low.

"Anyone can experience overheating, but those who are at most risk are either the very elderly and very young, so children and seniors tend to be most at risk," says Tim Smith, Pharmacy Practice Advisor with Pharmacists Manitoba. "It's a surprisingly wide variety of medications across a wide variety of different conditions. Some of the most notable ones are medications that might be considered, chemically speaking, anticholinergic. So, this can include a lot of different medications including some that are used for pain and sleep, like Amitriptyline, anti-psychotic medications, medications that help with bladder control and some antidepressants beyond the anticholinergic medications."

Smith lists more specific medications that could increase the risk of overheating during hot weather. Diuretics, also known as water pills, opioid pain medications, stimulants and a number of different blood pressure and cardiovascular medications can pose a risk.

He concludes that people with blood pressure and cardiovascular issues, depression, anxiety, schizophrenia and other mental health issues, pain and bladder control are likely to experience a low tolerance to hot weather.

"So, depending upon the medication, how they increase the risk for overheating can vary. In some cases, they can increase the amount of sweat someone has which can cause dehydration. In other cases, it can reduce the amount of sweat, which reduces how much heat they're able to dissipate through their skin. Medications, like water pills or diuretics, actually increase urine outputs, so that can cause someone to become dehydrated and then some medications work through different means altogether. So, reducing the amount of blood flow just under the skin or in the extremities in the body, or reducing the output of the heart. Interestingly, antipsychotics in particular and antidepressants can affect the part of the brain that regulates temperature control, so that's a completely different mechanism altogether."

Smith advises anyone who plans to go outside, whether they take these medications or not, should stay hydrated, avoid the hottest hours of the day, stay in the shade or indoors and take advantage of the air conditioning on hot days. He does not advise anyone to stop taking their medication to avoid these risks.

"The medications are prescribed for a reason. If they do have concerns about this, I'd suggest that they talk to their pharmacist or their prescriber to understand if there may be less risky options, but I definitely don't recommend that people stop their medications. Many medications don't necessarily work on an off/on switch type of effect, it requires consistency, and steady use to get the best benefits. So, we don't want to interrupt treatment just based on the weather outside."

Neurodiversity and Heat

Jillian Enright, Founder of Neurodiversity Manitoba, wrote a blog post about how neurodivergent people are at risk for overheating as well.

"I was seeing some misinformation or some incomplete information circulating online and I wanted to provide people with more in-depth, complete and accurate information so that they can make better-informed decisions and keep themselves safe during our hot summer."

Within the blog, Enright speaks of interception and how it affects neurodivergent people differently.

"Interoception impacts all of us. If you think of perception or 'ception,' it is how we perceive something and inter is like internal and so interception means how we perceive or experience the inner workings of our bodies. Essentially, it's the signals that our body sends our brain to alert us when something needs attention when we're hungry, thirsty, too hot, or too cold so that we can take action to meet whatever need that might be. So, in reference to the article, the interception was in the discussion of how neurodivergent people may be less likely to notice when they're starting to get a little thirsty or starting to get a little bit hot. For us, it might take us longer to notice, or until the feeling is more intense, and so that delay can put us at greater risk for overheating."

Enright says that neurodivergent people should take the same precautions as the general public, wear a hat and sunscreen and drink lots of fluids. However, there are other steps that she suggests.

"Some people like to use technology, set reminders for themselves to make sure they eat or drink or take breaks, or if you're going to be out with friends, you could ask somebody to remind you if they notice you're not really drinking much or ask you if you need a break in the shade or in the air conditioning. Some neurodivergent folks also have sensory issues with regard to taste and texture, so we are less likely to just drink water for the sake of drinking water. Some people really hate the taste of water and so it can be helpful to bring a special juice or even a smoothie to help keep your electrolytes balanced, one that you know for sure that you like and that you're going to drink."

She also notes that many neurodivergent people are on medications, antipsychotics and antidepressants, which is another factor that puts neurodivergent people at risk for overheating.