Extreme Heat Can Turn Common Medications Into Health Risks, MSU Doctor Warns

Temperatures so high they can be deadly have hit East Lansing the week of the Fourth of July holiday that will bring plenty of outdoor events to the region. 

While the heat impacts everyone, soaring temperatures into the 90s put individuals taking certain medications for mental health conditions, high cholesterol, weight loss and diabetes at an increased risk of a heat-related ailment — often without them realizing the risk. 

“The hard part is sometimes you don’t know you’re having a heatstroke or heat-related illness until it’s a little bit late in the game,” said Mark Smith, chief medical officer for MSU Health Care.

According to Smith, these medications primarily impact three areas: hydration, body temperature regulation and cardiovascular stress. When extreme weather hits, heat stress heavily exacerbates these underlying vulnerabilities. 

Mental health medications

Some of the most common mental health related medications used to treat anxiety and depression are Selective Serotonin Reuptake Inhibitors, or SSRIs, including Lexapro, Prozac and Zoloft. These medications block the brain from reabsorbing serotonin, a neurotransmitter that plays a critical role in regulating mood. 

However, Smith noted that these medicines also impact the body’s ability to regulate its internal thermostat. This disruption can lead to excessive sweating, or conversely, limit a person’s ability to sweat, resulting in rapid dehydration or overheating.

“Your body has the inability to identify and alter your temperature regulation as efficiently as it would if you weren’t on that medicine,” Smith said. 

For those taking an SSRI, this temperature disruption can increase the risk of serotonin syndrome – a condition where too much serotonin builds up in the system. Severe dehydration brought on by heat can exacerbate symptoms like sudden dizziness and confusion. 

Similar to antidepressants, stimulants also increase internal heat production. Stimulants often used to treat conditions like Attention-Deficit/Hyperactivity Disorder, or ADHD, increase the neurotransmitters dopamine and norepinephrine in the brain. 

Because they speed up bodily functions, they inherently generate internal heat, Smith said. This becomes concerning in hot weather, as the combination can spike a person’s heart rate, cause blood pressure issues and create additional cardiac load. 

Benzodiazepines — central nervous system depressants used to treat anxiety — cause a different kind of danger when someone overheats. Unlike stimulants, these drugs cause a significant mental status change. 

“Those are going to blunt your alertness,” Smith said. “Delayed recognition that you’re even over heating … not realizing that you’re hot … it’s sort of a domino, double-edge sword effect … it just gets worse because you’re not realizing it’s happening to you.” 

High cholesterol medications

It is more rare for high cholesterol medications like statins to cause heat-related issues but Smith noted that when they do, it is serious. 

Dehydration and heat stress can exacerbate rhabdomyolysis, a dangerous condition where muscle cells break down and the cellular debris enters the bloodstream, forcing the kidney to attempt to filter it out. Because this process can mask the early signs of heat exhaustion, it often goes unnoticed, Smith. 

Weight loss and diabetes medications

GLP-1 agonists are widely used by individuals managing type 2 diabetes or obesity. Smith explained that these medications work hormonally on receptors in and around the stomach, slowing the stomach from emptying so people feel full longer. 

“Essentially you delay your food absorption,” Smith said. 

Common side effects of these drugs include vomiting and diarrhea, both of which contribute to dehydration, Smith said. 

“You can dehydrate yourself just [by] being on the GLP-1 if you’re having severe side effects from them, so it makes it worse if you’re having that plus you’re in a heat-related situation,” he said. 

Recognizing and mitigating heat illness

There are three main stages of heat-related illness to watch for: heat cramps, heat exhaustion, and a heat stroke, Smith said. 

Heat cramps are painful muscle cramps that typically occur in the legs. 

Heat exhaustion can involve heavy sweating, feeling tired or weak, dizziness or headache. 

The most severe stage is heat stroke, which causes slurred speech, dangerously high body temperature, confusion and fainting. 

Mitigating symptoms when you first notice them is essential, Smith said. He notes there is a clear difference between an outdoor worker who is tired and sweating, and someone exhibiting signs of nausea, headache or dizziness when bending over. 

To stay safe this summer, Smith recommends keeping a water bottle nearby at all times. Taking steady sips throughout the day is far more effective than gorging on water. He also advises taking frequent breaks in the shade as soon as you notice heat-related symptoms. Finally, while it can be beneficial to take medication during the early morning or evening when temperatures are cooler, he recommends that patients should always consult their doctor first. 

To provide cover from the heat, East Lansing has opened the Hannah Community Center and East Lansing Public Library as cooling centers. The cooling centers will be open from Monday through Thursday. More information about the facilities and cooling center hours can be found on the city’s website.