7 things you should never leave in a hot car

While mineral sunscreens are typically OK in high temperatures, chemical sunscreens can lose certain filtering abilities when temperatures skyrocket. Yet according to Dr. Curt Littler, a dermatologist with Sharp Rees-Stealy Medical Group, mineral sunscreens are a better choice, anyway, as they offer more water- and sweat-resistance.

Medication that gets too hot can lose effectiveness or expire altogether. In fact, even the heat and moisture of a bathroom can cause damage. If you’ve had a medication in your car for quite a while, your best bet is to dispose of it. According to Ali Zanial, Sharp Grossmont Hospital’s director of Pharmacy, safe disposal of prescription medicine is important, so look for drug-takeback locations, certain eligible police stations or other solutions offered by the FDA.

Not all plastics are created equal. But, in general, you’re better off keeping plastic away from soaring temperatures. Substances found in some plastics can interfere with hormones, leading to serious health conditions, such as infertility or leukemia. According to Dr. Neelima Chu, a board-certified internal medicine doctor with Sharp Rees-Stealy, avoid heating food or drinks in plastic, whether that happens naturally in your car or if you use a microwave.

Frames on glasses can warp or melt, compromising the fit or putting pressure on the lenses. Additionally, some coatings on the lenses themselves can be negatively affected. That being said, keeping eyewear accessible and on your person is essential, especially prescription glasses for driving or sunglasses to protect from UV rays. According to Dr. Jennifer Tam, an optometrist with Sharp Rees-Stealy Medical Group, UV ray exposure can cause cataracts, macular degeneration and astigmatism. Keep your glasses protected in a case and tucked away from the sun’s rays or carry them with you.

Some forms of birth control can be impacted by temperature — cold and hot. Storing pills, patches, rings or condoms in a dry place at room temperature is the best way to ensure they won’t lose their effectiveness. Condoms, in particular, are best stored in a cool, dry place away from direct sunlight and the moisture associated with bathrooms.

The enemy of a tampon package is moisture. Like condoms, storing tampons in a hot bathroom is an often-unheard-of “no-no.” But the same goes for storing them in the car. Extreme heat could cause unwanted moisture, bringing mold and bacteria that can lead to infections or menstrual hygiene emergencies. Speaking of little-known facts, tampons expire. Most have a shelf-life of about five years.

Hand sanitizer is a must-have when navigating a season of respiratory illnesses, including COVID-19, flu and RSV. But storing it at high heat for a long period of time can cause the alcohol to evaporate, making it less effective in fighting viruses and bacteria. Instead of storing sanitizer in your car, consider travel-sized bottles that fit in your bag or containers with hooks that attach to backpacks.