General guidance is to change a liner every 3 to 5 hours, or sooner if it feels damp or you've been sweating. Liners are made for light moisture, spotting, or discharge, so they fill up faster than you'd think. Wearing the same one all day can trap moisture against your skin, which may feel less comfortable over time. If you're using Rael Organic Cotton Panty Liners, the same rule applies, swap to a fresh one every few hours and always change after a workout. Listen to your body, if something feels off, change it. And if you have any concerns about irritation or unusual discharge, check in with your doctor.