Attendees at the Chicanos Por La Causa Healthy Aging Spring Fair on March 20, 2025, in Phoenix. (Photo by Olivia Williams/Cronkite News)
PHOENIX – Simply walking from your front door to your mailbox in the summer heat can be dangerous, especially for older adults taking certain medications.
“As our body ages, our body’s ability to cope with the heat and respond to the heat changes,” said Mona Arora, assistant research professor at the University of Arizona College of Public Health.
Things can deteriorate quickly when medications from this Centers for Disease Control list are added to the mix of heat and age. The outcomes of this combination vary: Some stimulants, antihistamines, psychiatric and cardiovascular drugs can confuse the body’s ability to regulate temperature, while antifungals and antibiotics can increase the risks of sunburns.
Heat-related deaths are becoming more common, especially in Arizona, where the temperatures have grown significantly hotter each year. Extreme heat is the leading cause of weather-related deaths, followed by rip currents and tornadoes.
Older adults with common chronic conditions – many of whom take medications that increase their vulnerability to heat – face growing risks, especially as exposure becomes harder to avoid.
More than 66% of heat-related illness hospitalizations were in combination with cardiovascular diseases, according to the Arizona Department of Health Services.
A group of people gathered around a blue table outdoors, with a woman and man leaning forward, and others standing nearby.
Consuelo and Ipolito Gutierrez at the Chicanos Por La Causa Healthy Aging Spring Fair on March 20, 2025, in Phoenix. (Photo by Olivia Williams/Cronkite News)
However, the relationship between heat and medication is complicated.
“It’s not that one-to-one relationship (in which), ‘I’m on this medication so I’m at an increased risk,’” Arora said. “It’s not just the medication itself but it’s also these other driving factors like not being able to recognize that ‘hey, I’m thirsty.’”
Some medications disrupt thermoregulation and fluid balance, heightening the risks associated with hot weather. Diuretics, which cause people to urinate more frequently, can reduce thirst, whereas antidepressants and antipsychotics might hinder sweating.
“So if you’re already in a pre-dehydrated state and you go out and are more susceptible to heat, that’s going to cause you to be less resilient,” said Brian Drummond, an emergency physician and clinical professor at Banner University Medical Center in Tucson and a member of the Heat and Medications Task Force, a statewide effort to raise awareness on how medications affect heat risks.
Drummond also noted that medications can interfere with cognition and mental status, affecting the ability to make “good” decisions: “If you know you’re in the heat, get out of the heat. You have to make that cognitive decision: ‘I’m going to leave this hot area and find a cooler place to be.’”
Every year, Drummond sees patients who are sick from the heat, and the reasons vary. Some patients donate plasma, for example, to generate income and then walk to the bus stop where they end up vomiting and fainting, Drummond said.
A study published in the National Library of Medicine investigated the connection between heatwaves, common medications for chronic conditions and the risk of heat-related hospitalization for people on Medicare.
The authors recommended changes to prescription guidelines, drug labeling policies and how the public is informed during heat waves.
Arora, who is also a part of the Arizona task force to raise awareness on how medications mix with heat risks, suggested patients be proactive.
An elderly person in a wheelchair clapping next to green and gold balloons indoors.
An attendee at the Chicanos Por La Causa Healthy Aging Spring Fair on March 20, 2025, in Phoenix. (Photo by Olivia Williams/Cronkite News)
“We encourage people to seek out their local pharmacist, to seek out their doctor. Talk to them, especially now as we get into heat season … because they can look at your own individual history … and be able to give you more specific information on, if you have medications that cause dehydration, how much more water is that you really should be (drinking),” Arora said.
Pima County in southern Arizona is developing a year long analysis of heat-related deaths and prescription histories, according to Mark Person, public health program manager for the Pima County Health Department.
The analysis examined medical records sent to the medical examiner’s office from hospitals and primary care doctors.
Although the findings have not been published yet due to data requirements, “we already know that the drugs increase the risk of hyperthermia (when the body’s temperature rises), but we do not know how often people who die of hyperthermia are also taking these medications,” Person wrote in an email to Cronkite News. “If we can answer this question, it will help us expand upon traditional heat safety messaging.”
The task force created an information sheet for health care providers with questions for patients to help mitigate heat risks and recommendations to assess medications or dosages.
“We want people to be aware of what the risks are so that they can plan accordingly. If they’re prescribed medications, the best course of action is to continue taking it but to also have these discussions with their providers and think through ways they can protect themselves in the heat,” said Jennifer Botsford, bureau chief for environmental health at the Arizona Department of Health Services and Arizona task force member.