No matter what the source, urine on a mattress poses an unfortunate problem. A little effort is involved, as you cannot simply toss a mattress into the washing machine. As daunting as the chore may seem, for health and sanitary reasons, it's important to clean up any urine on a mattress. Fortunately, with the proper know how, the task is easily accomplished.
Blot up as much of the urine as possible with paper towels or an old towel. Be careful not to press too hard and push the urine deeper into the mattress.
Cover the area with baking soda. This serves two purposes; it helps draw excess moisture out of the mattress, and aids in odour removal.
Vacuum up the baking soda after it has been left to sit for at least an hour.
Mix vinegar and water in a spray bottle in equal parts and spray the affected area. Use a clean cloth to scrub the stain. Vinegar helps to freshen fabrics, and also helps with odour removal. Scrub the area, being careful not to saturate it until no trace of urine is left.
Set the mattress outside to dry in the sunshine. Sunlight is highly effective in curbing odours and killing germs. If weather doesn't permit, place a fan nearby so that air can circulate over the mattress and help it dry.
Wear gloves when dealing with urine.
Do not put bedding back on the bed until it is completely dry, or mould may grow on or within the mattress. Never use ammonia on a cat urine stain; they smell similar, and the cat may repeat the atrocity to mark territory.