A pharmacist has urged anyone using these medicines to take extra care.Ben Hurst and Georgia Burns Trainee Trends, Showbiz and Lifestyle Writer
19:43, 26 May 2026
Soaring temperatures could spell danger for some people on antidepressants(Image: GettyImages)
A health warning has been issued for people taking certain medications, with experts warning they could suffer harmful side effects as temperatures continue to rise across Scotland. A pharmacist has urged anyone using these medicines to take extra care as the country prepares for another spell of unusually warm weather.
Scotland recorded its hottest day of the year so far on Monday after temperatures climbed well above the seasonal average during the bank holiday weekend. However, forecasters believe the record could be broken again later this week, with highs of 27C expected in some parts of the country on Thursday.
The soaring temperatures brought clear skies and sunshine to much of Scotland, with many people flocking outdoors and reaching for sunscreen to enjoy the rare burst of heat. Some areas experienced temperatures as much as 12C higher than what is normally expected for late May.
The previous warmest day of the year had been recorded on April 30, when temperatures reached 24.7C. That figure was passed on Monday after Charterhall in the Scottish Borders climbed to 26.6C.
Temperatures in Scotland are set to soar this week – but people on some medications need to take extra care(Image: Ken Jack/Getty Images)
Elsewhere, Royal Botanic Garden Edinburgh recorded 25.5C by late afternoon, while Leuchars reached 25.4C and Aboyne saw temperatures peak at 24.9C.
Forecasters say the warm conditions are expected to continue throughout the week, with temperatures likely to climb even higher in the coming days.
While the sunshine has been warmly welcomed across Scotland after weeks of dull weather, experts have warned the soaring temperatures could post risks for people taking certain medications, including antidepressants.
Dipa Kamdar, Senior Lecturer in Pharmacy Practice at Kingston University, wrote on The Conversation website that: “The body uses several mechanisms to regulate temperature: sweating, blood flow to the skin and fluid balance. But some commonly prescribed drugs interfere with these processes, making it harder to stay cool.”
She reviewed a variety of medications commonly prescribed throughout the UK, stressing the need for extra vigilance.
Antidepressants
Ms Kamdar highlighted two specific categories of antidepressants – selective serotonin reuptake inhibitors (SSRIs) and tricyclics (TCAs) – as potentially making summer conditions harder to tolerate. These might include sertraline, fluoxetine (Prozac), and citalopram amongst SSRIs, while TCAs encompass amitriptyline, nortriptyline, and lofepramine.
She explained: “They could even cause heat intolerance due to how they affect the body’s ability to sweat.” These antidepressants are thought to function partly by influencing neurotransmitter levels in the brain, primarily serotonin and noradrenaline. This may lead to some patients sweating less, which during hot weather could make it difficult to cool down.
TCAs also elevate noradrenaline levels, a neurotransmitter that activates sweat glands. This can lead to increased perspiration. Indeed, both SSRIs and TCAs can cause heightened sweating in those taking them. Evidence suggests up to 14 per cent of antidepressant users encounter this side-effect.
SSRIs may also disrupt the hypothalamus, the brain area responsible for regulating body temperature and instructing sweat glands to begin producing sweat. However, this signal may be impacted by elevated serotonin levels.
Ms Kamdar clarified: “Since sweating is a key cooling mechanism, any disruptions to this process can lead to heat-related illness. Excess sweating may also cause dehydration if fluids aren’t replaced.”
Antipsychotics
Scots must be careful if they are taking these medications during the sun(Image: PA)
Ms Kamdar explained: “Antipsychotics are used to treat psychosis, which can occur in schizophrenia and bipolar disorder. They do this by blocking the neurotransmitter dopamine – which in turn affects levels of the neurotransmitter serotonin. This can disrupt the hypothalamus’s ability to sense and respond to changes in body temperature.
“As a result, someone taking an antipsychotic might not feel overheated or thirsty when it’s warm outside. This can result in low blood pressure and diminished heart function.
“The body then attempts to compensate by constricting the blood vessels and retaining heat. This consequently reduces perspiration and makes it more challenging to cool down effectively.”
Heart medications
Beta-blockers work by slowing the heart rate and reducing the force with which the heart pumps blood. However, Ms Kamdar pointed out that this can restrict blood flow to the skin, making it increasingly difficult for the body to dissipate heat during warm weather.
She further explained: “Diuretics are also commonly used in the treatment of high blood pressure or heart failure. But as these drugs increase urine output, this may lead to dehydration and electrolyte imbalances during hot weather.
“With less fluid available, the body may struggle to sweat properly. If you become severely dehydrated, you might actually stop feeling thirsty. Blood pressure can also drop, which may cause dizziness or fainting – especially when standing up.”
She also highlighted that blood pressure medications such as Ramipril and Losartan can heighten the risk of dehydration. “These drugs block a system in the body that helps control blood pressure, fluid balance and thirst. This may reduce your natural urge to drink, increasing dehydration risk when it’s hot.”
Stimulants
Often these medications interfere with regulating temperatures(Image: Getty Images)
Prescribed amphetamines for ADHD, for instance, interfere with several brain chemicals, including dopamine and noradrenaline. These effects can elevate body temperature, speed up metabolism and distrupt the body’s ability to sweat, making it increasingly difficult to cool down, particularly during physical activity or in warm conditions.
This could potentially result in dehydration, overheating or even heatstroke. Stimulants may also mask feelings of fatigue, leading people to push themselves without recognising the danger.
Insulin
Ms Kamdar explained: “Warm temperatures cause the body’s blood vessels to dilate (widen) to aid in cooling off. However, this process results in faster absorption of insulin into the bloodstream due to increased blood flow to the area where insulin is injected – causing blood sugar levels to drop more rapidly.
“This can result in hypoglycaemia (low blood glucose level), potentially causing symptoms such as dizziness, shaking, sweating, irritability, and even loss of consciousness or seizures.
“Heat can also degrade insulin, reducing its effectiveness and making it unsafe. This is why insulin should be stored in the fridge until use – especially in summer. Damaged insulin will change appearance – turning cloudy or changing colour.”