Things You'll Need
Liquid laundry detergent
While sweating serves a purpose for your body, keeping your body temperature controlled and balancing electrolytes, it may also cause embarrassment if it becomes obvious through perspiration stains and odors on clothing. Although nylon is a synthetic fabric that is durable, it is not immune to the effects of perspiration. Salvage your underarm-odor-tainted nylon shirt, rather than tossing it due to the off-putting smell it emits.
Pour a small amount of liquid laundry detergent on the underarm area of the nylon garment. Rub the perspiration-stained area gently to distribute the detergent thoroughly over the surface of the stain. Allow the detergent to remain on the nylon fabric for approximately 20 minutes.
Wash the nylon garment as you normally would, in warm water with the regular amount of detergent, once the pretreatment has sat for 20 minutes. Use an extra rinse cycle to make sure all detergent is removed.
Hang the garment to dry. The heat of a dryer cycle may cause the odor-causing stain to set, which will make it harder to remove if some remains. Additionally, heat may melt the nylon fibers and irreparably damage the item.
Sniff the underarm area of the nylon garment once dry. If it still smells like perspiration, lay it flat and sprinkle it liberally with baking soda. Allow the baking soda to absorb the underarm odor for 12 to 24 hours, then shake and launder again to remove baking soda residue.