Overview

• Temperatures above 25 °C can alter the chemical stability of many drugs and reduce their intended efficacy.
• Heat damage often goes undetected, compromising dosage accuracy in products like asthma inhalers.
• High temperatures can intensify the effects of blood pressure medications and transdermal patches and trigger dizziness or fainting.
• Harvard specialists highlight that antidepressants, diuretics, anticholinergics, opioids and sedatives heighten risks of heat stroke, circulatory collapse and renal issues.
• Patients are advised to transport standard medications in shaded vehicle areas, to use cooler bags for cold-chain drugs held at 2–8 °C, and to discard any suspect heat-damaged doses.