Extreme Heat and Medication: Safety Tips and Risks Explained

Extreme heat can increase the risk of heat-related illnesses and subtly threaten health by intensifying the side effects of many common medications. Hot weather can also damage medicines like insulin that need refrigeration. Inhalers might explode, epinephrine injectors such as EpiPens can malfunction, and meds delivered by mail can deteriorate.

Medications Affected by Heat

Blood pressure pills that reduce fluid in the blood can lead to dehydration. Beta blockers for heart conditions can decrease blood flow to the skin, making you less aware of dangerous heat. Some antidepressants can hinder your ability to stay cool. Aspirin and other over-the-counter pain relievers decrease fluid and sodium levels, making it harder to deal with high temperatures.

Additionally, the combination of heat and drug side effects can cause lightheadedness and falls. Alcohol increases this danger, according to pharmacist Bradley Phillips from the University of Florida College of Pharmacy. "You might be on antibiotics, not think too much of it, go down to the beach and then come back with a whopping sunburn," said Dr. Mike Ren from Baylor College of Medicine in Houston.

Storing Medications During Travel

Medication should generally be kept in a cool, dry place unless it needs refrigeration. This can be challenging while travelling. Before a summer road trip, check labels for storage requirements. Carry medicine in a cooler when travelling by car, even if it doesn’t require refrigeration. The car’s trunk or glove box could get too hot for even room temperature storage.

If travelling by plane, keep medications in your carry-on bag in case your checked luggage is delayed or lost, as it can get too cold in the cargo hold. Mail-order pharmacies are responsible for keeping your drugs at safe temperatures during storage and transit. The best practice is to ship sensitive medicine in special packaging with ice packs and temperature monitors.

Mail-Order Prescriptions

However, this doesn’t always happen. Or a delivery can come at a bad time, said Ren, who recently helped his vacationing mother by bringing her delivery of supplements into her Houston home as the region faced soaring heat. "If you know you’re going to be at work all day, or if you’re on vacation, and you get medications delivered, you definitely don’t want that sitting outside in the hot 100-degree sun," Ren said.

If you think your mail-order medication has been damaged by the heat, call the pharmacy to report the problem. You can learn more about your medication’s side effects and storage requirements at the National Library of Medicine’s MedlinePlus website or talk to your doctor or pharmacist.

Research Needs

Researchers in the US and Australia say some common warnings about heat and drugs lack scientific evidence. Ollie Jay from the University of Sydney found support for only four out of 11 medication categories listed by the World Health Organisation as concerns with high heat.

Dr. Renee Salas from Massachusetts General Hospital emphasised that as climate change accelerates, there’s a need to know which medicines are riskiest in the heat. "We don’t have that answer yet, and it’s one that we need to rapidly figure out," Salas said.

Phillips recommends staying hydrated and not relying on your body’s ability to tell you when you’re thirsty. He advises asking your doctor or pharmacist about how much water you should drink if you're on medications that increase dehydration.

Some medicines like antibiotics, antifungals, and acne drugs can heighten sensitivity to the sun, causing rashes and sunburns. If taking these medications, stay under an umbrella or wear sun-protective fabrics and sunscreen.

Changing behaviour rather than medications is suggested by Jay: "Be a bit more cautious," he said. Staying out of the heat is advisable when possible.

The impact of extreme heat on medication efficacy and safety is a growing concern that requires further research to ensure public health safety.