To get stains out of underwear, soak them in a solution of cold water and oxygen-based bleach, and allow the bleach to work into the stains by leaving the underwear overnight. Even some of the most stubborn spots from bodily fluids tend to dislodge after an all-night soaking.
- Make the bleach solution
Mix cold water and oxygen-based bleach, such as Purex 2 Color Safe Bleach, Country Save Bleach, Clorox 2 or OxiClean, using the ratio from the package instructions to create the solution.
- Soak the underwear in the solution
Press the underwear down into the solution completely, making sure that the garments stay completely submerged. Keep them in the solution for a minimum of 8 hours. Make sure the container is large enough to allow each garment free movement and exposure to the solution. Do not disturb the garments until the full soaking time has elapsed.
- Check the stains after soaking
Remove each garment from the solution, and examine carefully for stains. Throw the garments into their usual load in the washing machine if the stains are out, but repeat the process with a fresh mixture of oxygen-based bleach and water if the stains remain. Repeat the process as needed to get the stains out.