A pharmacist has issued a warning to anyone who takes these five different kinds of drugs – and gives advice on how to avoid problems as temps to hit 34C
A health warning has been issued regarding five specific types of medication that can potentially cause complications during hot weather. A pharmacist has advised patients on these medications to take extra precautions as temperatures are expected to rise this week, with Monday predicted to be the hottest day of the year so far.
The UK braces for another scorching day as a second amber heat health alert continues. The Met Office forecasts highs of 30C in London, with eastern England and the Midlands not far behind at 28C.
Monday could see temperatures reaching an extreme 34C, marking only the fourth instance of such heat in June since the 1930s.
On The Conversation website, Dipa Kamdar, Senior Lecturer in Pharmacy Practice at Kingston University, explained: “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 emphasised that people should keep taking the medications – but that they need to take measures to ensure they don’t have an issue.
She reviewed various widely used medications in the UK, emphasizing the need for users to act accordingly.
Antidepressants.
“Both these antidepressants are believed to partly work by affecting neurotransmitter levels in the brain – primarily serotonin and noradrenaline. However, they may also affect other neurotransmitters. For instance, TCAs can block acetylcholine, a neurotransmitter important for sweating. This may cause some patients to sweat less. On a hot day, this could make it hard to cool down.
“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.
“As a result, someone taking an antipsychotic might not feel overheated or thirsty when it’s hot out. This can cause low blood pressure and reduced heart function. The body then tries to compensate by narrowing the blood vessels and holding in heat. This in turn reduces sweating and makes it harder to cool down properly. Additionally, antipsychotics have anticholinergic properties. This means they block the action of acetylcholine, making it harder to sweat.”
Heart medications.
She added: “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.”
Ramipril and losartan, also used to manage blood pressure, can increase the risk of dehydration as well, she said. “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.
Stimulants – such as the amphetamines used for ADHD – affect many brain chemicals, including dopamine and noradrenaline. This can increase body temperature, boost metabolism and change how the body sweats – all of which can make it harder to cool down, especially when exercising or in hot weather. This can also potentially lead to dehydration, overheating or even heatstroke. Stimulants may also reduce the feeling of tiredness, which can cause people to overexert themselves without realising the danger.
Insulin.
Ms Kamdar said: “Warm temperatures cause the body’s blood vessels to dilate (widen) in order to help us cool off. But this action means insulin is absorbed into the bloodstream faster as there’s enhanced blood flow to the area where insulin is injected – making blood sugar drop more quickly. This can lead to hypoglycemia (low blood glucose level), which may lead to dizziness, shaking, sweating, irritability and even potentially 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.”
How to prevent heatstroke.
- Always check labels for storage guidelines. Avoid leaving medications in hot locations, such as inside cars or on windowsills.
- Insulin isn’t the only medication that can be affected by heat – inhalers and EpiPens can also malfunction or become less effective.
- Ensure you stay hydrated when it’s warm – unless your doctor has advised against it. Dehydration can actually exacerbate the effects of many medicines.
- For instance, anti-inflammatory painkillers (like ibuprofen) are more likely to cause kidney issues and bipolar medicines (including lithium) can become toxic if you’re dehydrated.
- Avoid the hottest parts of the day and try to stay in cool environments whenever possible. Be vigilant for warning signs of heat-related illness – such as dizziness, confusion, nausea or excessive sweating.
- Never stop taking your prescribed medication without seeking medical advice. If it’s impacting your ability to handle the heat, consult with your doctor or pharmacist.
To read the full article on The Conversation click here.