Treat friction rash, otherwise known as chafing, by first cleaning and drying the area, and then apply petroleum jelly or a medicated ointment. This helps protect the skin from bacteria while preventing further irritation.
After treating the affected area, take preventative measures against further chafing to give the skin time to heal and avoid infection. Keep the skin dry with talcum powder or moisture-wicking clothes, and lubricate problem areas if necessary with petroleum jelly or any preferred lubricant. Chafing is caused when the skin is repeatedly or rapidly rubbed, especially if the skin is moist, and common problem areas include between the thighs, under the armpits and on the nipples.