Publisher Health

Melted capsules. Cloudy insulin. Pills that may no longer work.

Doctors and pharmacists say the scorching temperatures enveloping the country could be endangering people’s health in an unexpected way: by overheating their medications.

Millions of Americans now receive their prescription medications through mail-order shipments, either for convenience or because their health plans require it. But the temperatures inside the cargo areas of delivery trucks can reach 150 degrees Fahrenheit in the summer, according to drivers — far exceeding the range of 68 to 77 degrees recommended by the national organization that sets standards for drug handling.

Mail-order pharmacies say that their packaging is weather resistant and that they take special precautions when medication “requires specific temperature control.” But in a study published last year, independent pharmaceutical researchers who embedded data-logging thermometers inside simulated shipments found that the packages had spent more than two-thirds of their transit time outside the appropriate temperature range, “regardless of the shipping method, carrier, or season.”

Extreme temperatures can alter the components in many medications, from pancreatic enzymes to the thyroid replacement drug levothyroxine to oral contraceptives, medical experts say.

Dr. Mike Ren, a primary care physician and an assistant professor in the department of family and community medicine at the Baylor College of Medicine, said that liquid medications like insulin or AUVI-Q, the epinephrine injection for allergic reactions, are often at heightened risk of degradation because excessive heat exposure can cause the evaporation of liquid components that were compounded at precise ratios. Aerosolized medications, too, are uniquely vulnerable because of the risk of pressure changes in the canister.