Corn starch has been used for generations as method of preventing or helping to soothe diaper rash and other skin rashes. For mild skin irritations, corn starch is a good alternative to talcum (baby) powder. Corn starch can provide temporary relief for anything from chicken pox to poison ivy.
Wash the area with cool, clean water. Wipe gently with a wash cloth and use a mild soap so as not to irritate the skin. Use cool water, especially with poison ivy, to prevent the spread of the rash. Rinse with cool water. Pat dry.
Allow the affected area to air dry for a few moments and then sprinkle lightly with corn starch. Cover with a cotton cloth, or for diaper rash, a clean, dry diaper. For diaper rash, be certain to change the diaper often to prevent additional rash.
Monitor the progress of the rash. If using corn starch to treat diaper rash, be sure to note if the rash is getting worse. Some diaper rashes are caused by yeast infections which can be made worse by corn starch.
Identify the type of rash. If the rash is simply a heat rash or mild irritation from encountering an allergen, the rash should heal rather quickly. Discontinue treatment with corn starch and see your medical professional, if the rash is widespread, concentrated in the groin and arm pits, or develops blisters or sores.
Take a cool bath. If the rash is a result of measles or chicken pox, taking a cool bath with 1/2 cup of oatmeal added to the bath water can help begin the process of drying our the rash. After the bath, pat dry with a clean, dry towel and apply a light coat of corn starch to the rash-covered areas.
If the rash persists or worsens, consult a medical professional.