How to Remove Underarm Stains on White Shirts

Pour 1 tbsp. of heavy-duty laundry detergent onto the perspiration stains. Rub the detergent into the stain.

Lay the shirt on a clean table in the sun, with the sun's rays shining on the detergent and stains. Allow to sit in the sun for three to four hours. Keep the shirt damp by misting with a spray bottle.

Place the white shirts in the washer and launder with heavy-duty detergent in cool water. Allow to air dry.

Mix a solution of half hydrogen peroxide and half water in a bowl. Pour the solution onto any perspiration stains not removed during washing. Allow the hydrogen peroxide solution to remain on the white shirts for 30 minutes. Launder in cool water and detergent, and allow to air dry. Soak the perspiration stains in full-strength hydrogen peroxide for 30 minutes if the stains remain.

Create a cleaning paste by crushing three aspirins and mixing them with 1 tbsp. of cream of tartar and 1 cup of warm water. Apply the paste to stubborn perspiration stains with an old toothbrush. Scrub the stains, then rinse in a sink of warm water. Continue scrubbing with the paste and rinsing the fabric until all stains are removed. Launder the shirts with detergent, and allow to air dry.