People need to take extra caution this week amid soaring temperatures
On June 23, 2026, the UK Health Security Agency (UKHSA) issued advice to UK residents. It warned about the heatwave and the associated health risks as temperatures soar.
Officials issued advice on “how to keep cool and stay well during hot weather”, highlighting that some medications may cause problems in high temperatures. It also encouraged people to read guidance on why some people suffer more during heatwaves and to take extra care.
It explains: “Medications commonly taken for chronic conditions, such as diuretics, beta-blockers, or drugs used to treat mental health issues (like antipsychotics and common antidepressants like SSRIs), can also alter the body’s ability to cool itself or keep fluids, making people even more susceptible to complications.”
People on certain medications may need to be on alert
Rethink Mental Illness explains that selective serotonin reuptake inhibitors (SSRIs) are a type of antidepressant. It notes that SSRIs and SNRIs can cause excessive sweating, which is a common side effect that can affect how the body regulates temperature.
SSRI examples include:
- Citalopram
- Fluoxetine
- Sertraline
- Paroxetine
SNRIs (serotonin-norepinephrine reuptake inhibitors) are similar to SSRIs and include:
Can antidepressants cause heat exhaustion?
Rethink says yes, it can. It confirms in some cases, antidepressants and heat intolerance can increase the likelihood of:
- Heat exhaustion
- Dehydration
- Heat stroke (in severe cases)
This is more likely if you:
- Are older
- Take multiple medications
- Spend long periods in hot environments
Other medication and hot weather
The UKHSA advises understanding how your medication may affect your body’s response to heat. It recommends checking the guidance and speaking to a doctor or pharmacist if you have any concerns.
It continues: “In this way, hot weather doesn’t just present a risk of heat-related illness, but can act to worsen existing health conditions, an often overlooked but critical part of why some people may suffer more than others during heatwaves.”
It adds: “It’s important to understand that high temperatures can also worsen existing health conditions, sometimes with serious consequences.
“People with conditions including, but not limited to, cardiovascular, respiratory, kidney problems or who are on certain medications may not just be vulnerable to heat in general, they may experience a worsening of their underlying illness during a heatwave.
“This happens because when the body tries to cool itself down, it puts additional strain on organs that may already be under pressure. For example, people with heart disease may find it harder to maintain adequate blood flow, leading to chest pain or even heart failure.
“Similarly, people with chronic obstructive pulmonary disease (COPD) or asthma may struggle to breathe as hot air, pollution, and dehydration combine to inflame the airways and reduce oxygen intake.
“Those with kidney disease or diabetes are at increased risk of acute kidney injury when dehydrated in hot weather, as the kidneys become less effective at regulating body fluids.”
For more information on medication and hot weather, visit Rethink Mental Illness. If you are worried, always speak with your doctor.