Try using natural (crystal) deodorant or tea tree oil-based deodorants. You can also get these underarm clothing protectors at your local Sewing/Crafts store (they're called "Disposable Dress Shields" and can be found
here).
To remove the stains, use oxyclean (or similar oxygen-based product) and soak it before washing. Machine drying the stains (e.g., dryer) will also set the stains in. If you really want to prevent them from getting worse, air dry your shirts.
Here you go... More info from:
http://www.oxxousa.com/garment_care.htm
Condition Yellow:
How to avoid those unsightly underarm stains
When you're trying to look your best, even the smallest clothing stains can be embarrassing. But none are as potentially humiliating as yellow underarm stains.
One would think these are caused by perspiration ? but one would be wrong. While it is true that the chloride salts in perspiration tend to fade all colors, it is the combined effect of sweat and deodorant or antiperspirant buildup that yellows fabric. Acidic antiperspirants contain aluminum chloride, which can change the color of some dyes.
To prevent deodorants or antiperspirants from tainting your clothes, follow these steps:
*Use alcohol-free deodorants with a natural pH rather than an acidic antiperspirant. Avoid deodorant products that contain acidic solutions of aluminum chloride.
*Apply the product as instructed, and avoid overuse.
*Allow the product to dry before dressing.
*Avoid prolonged contact with antiperspirants and deodorants.
*Use underarm guards when wearing delicate garments, especially those made of silk.
If discoloration does occur, don't hesitate to take the item to your dry-cleaner immediately and point out the problem. This can help prevent further damage to the item.
You can remove residue from washable garments by washing them as soon as possible after you wear them, using the hottest water safe for the fabric. First, check the label on your laundry detergent for pretreatment instructions. Then, pre-treat the stains by soaking the garment in a detergent containing enzymes.
If the stain remains, you can try using three percent hydrogen peroxide or chlorine bleach according to fiber type. However, read care label instructions first. Also, before trying this method, test for colorfastness by applying the bleach to an unexposed area, and let stand for five minutes. If the color is affected, do not use the product.
Don't let unsightly yellow underarm stains ruin your clothing ? or your reputation. Use deodorants or antiperspirants correctly.
[ e d i t ]
Fixed link.