SSRIs create a challenge during the summer heat, pharmacists warn

Some common medications can increase your risk of heat-related illness during summer

Shelby Ebertowski, KSAT Weather Authority Meteorologist

Published: July 10, 2026 at 6:18 PM

As temperatures continue to climb across South Central Texas and summer heat settles in, health experts are reminding residents that certain medications can make it more difficult for the body to stay cool, potentially increasing your risk for heat-related illnesses.

That warning could affect millions of Americans. Studies estimate that roughly one in six adults take an antidepressant, making them among the most commonly prescribed medications in the United States.

Erica Torres, a pharmacist through University Health, said antidepressants can interfere with the body’s natural ability to regulate temperature because they affect serotonin, a brain chemical that plays multiple roles throughout the body.

“When we think about our antidepressants, a lot of it works up here,” Torres said, referring to the brain. “Serotonin is a really important piece of how our medications for depression work. But serotonin also has a job in temperature regulation. So depending on the medication, it can disrupt different ways for us to cool our body down.”

The human body is constantly working to maintain a safe internal temperature, especially during hot weather. However, certain medications can make that process less efficient, making it more difficult to recognize when the body is overheating.

“When we’ve got a medication we’re taking that ends up disrupting that system a little bit, that can then cause some problems as far as, ‘Am I overheating, or is that just a normal part of me being on this medication?’” Torres explained.

One common side effect patients may notice is a change in how their body sweats.

“With patients on antidepressants, we see issues with excessive sweating, and the ability to not cool themselves down as much and as quickly,” she said.

Antidepressants aren’t the only medication that can increase heat-related risks. Pharmacists say several other commonly prescribed drugs can also make people more vulnerable during periods of extreme heat, including:

Diuretics, which can increase the risk of dehydration
Blood pressure medications, which may affect how the body responds to heat and fluid loss
Stimulant medications, which can increase body temperature or reduce heat tolerance
Other medications that may interfere with sweating or hydration

“There are so many different reasons,” Torres said. “Just thinking about our blood pressure medications, the primary way we are more susceptible is the dehydration piece.”

Experts say the most important thing people can do is pay attention to their body’s warning signs before heat exhaustion or heat stroke develops. Symptoms such as dizziness, confusion, nausea, excessive sweating, lack of sweating, rapid heartbeat, muscle cramps or unusual fatigue should not be ignored, especially during prolonged outdoor activity.

Healthcare providers also stress that patients should never stop taking prescribed medications without first talking to their doctor or pharmacist.

“These medications are great — they’re lifesaving,” Torres said. “But sometimes they can come with a side effect of sweating.”

If you’re taking prescription medications and plan to spend time outdoors this summer, pharmacists recommend staying well-hydrated, taking frequent breaks in the shade or air conditioning, avoiding strenuous activity during the hottest parts of the day and discussing any concerns about heat sensitivity with your healthcare provider.