Urine stains on carpet can be frustrating to remove, especially if the stains are old. As the urine soaks down into the fibers of the carpet, removal is more challenging than with fresh stains. Whether from a dog, cat or person, old urine stains on carpet will not only leave an unsightly mark but also an unappealing odor. Removing old urine stains will freshen the look and smell of the carpet.
Fill a clean spray bottle with equal parts white vinegar and lukewarm water. Shake the bottle to combine the ingredients. Do not use hot water, which can sets the stain into the carpet fibers.
Spray a generous amount of the solution directly onto the stain. Apply enough to saturate the carpet, allowing it to reach the full depth of the fibers.
Use a soft-bristled scrub brush to work the mixture into the carpet. Alternatively, you can scrub the carpet with your fingers (wearing a latex glove is a good idea).
Let the mixture to sit for about 30 minutes, then blot the solution from the carpet using clean rags or paper towels. Apply heavy pressure with your fists or step on the rags to soak up as much liquid as possible. Allow the carpet to air-dry.
Sprinkle a liberal amount of baking soda over the affected area of the carpet once it has dried from the vinegar solution.
Mix ½ cup hydrogen peroxide and 1 tsp. dish soap into a bowl (see warning, below). Pour the mixture on top of the baking soda and work it into the carpet using your fingers. Follow up by scrubbing the area with a scrub brush.
Allow the mixture to dry completely onto the carpet. Vacuum the carpet to remove the baking soda powder.