Period panties, also known as menstrual underwear, are absorbent undergarments designed to be worn during menstruation. They are made of highly absorbent fabrics that can soak up menstrual blood, and the outer layer usually includes nylon and Lycra, finished with a liquid-repellent film. Period panties are designed to be worn like regular underwear, but they can hold one to two tampons worth of flow. They are considered to be an eco-friendly way to cut down on waste and reduce spending on disposable menstrual products like pads, tampons, and liners. Period panties are available in different cuts like high-waisted, bikini, hipster, and thongs, and some brands come in different levels of absorbency. It is recommended that period panties should be changed every 8-12 hours to avoid leakage and infection. Period panties do not stop the flow of menstrual blood, so some women use them alongside other products like tampons or menstrual cups to add another layer of protection.